{"product_id":"hella-355123122-vented-brake-rotor-320mm-6x112","title":"Hella 355123122 Vented Disc Brake Rotor, 320mm 6x112","description":"\u003cp class=\"nvn-hero\"\u003eThe Hella 355123122 is a vented, one-piece disc brake rotor built to Hella's fit-and-forget standard. It measures 320 mm across with a 28 mm nominal thickness, a 68 mm hub bore, and a 6 x 112 mm wheel bolt pattern. Zinc-coated gray cast iron keeps surface rust down. Sold individually, so order the pair if you're doing both sides of the axle.\u003c\/p\u003e\n\n\u003cdiv class=\"nvn-description\"\u003e\n\u003cp\u003eThe Hella 355123122 is a vented, one-piece disc brake rotor, and it's built the way Hella builds everything: fit it, forget it, and let it do its job for years. This is the friction surface that turns your vehicle's momentum into heat every time you press the pedal, so the material, the cooling, and the fit all matter. Hella's part number here is 355123122, and it's sold as a single rotor.\u003c\/p\u003e\n\u003cp\u003eStart with the size. The rotor measures 320 mm across the outside diameter, which is a little over 12.5 inches, with a 28 mm nominal thickness. That's a large swept area, and a large swept area means more surface for the pads to grab and more mass to soak up heat before the rotor gets hot enough to fade. The 68 mm hub size is the center bore, the machined opening that slides over your hub so the rotor runs true. Get that seating right and you won't chase phantom vibrations later.\u003c\/p\u003e\n\u003cp\u003eThe wheel bolt pattern is 6 x 112 mm. That's a six-lug pattern on a 112 mm circle, and it's the single most important number to confirm before you order. Hold this rotor up against your current one, count the lugs, measure the circle, and match the 320 mm diameter and 28 mm thickness. If all four numbers line up, bolt pattern, hub bore, diameter, and thickness, you're in the right place. If any one of them is off, it's the wrong rotor for that corner, and no amount of muscle will make it fit correctly.\u003c\/p\u003e\n\u003cp\u003eNow the design. This is a vented rotor, not a solid one. Vented means there are internal cooling vanes cast between the two friction faces, and those vanes act like a centrifugal fan when the wheel spins. Air pulls through the middle and carries heat away. That's what you want on a vehicle that sees real stopping loads, towing, grades, stop-and-go traffic, or just a heavier platform, because heat is the enemy of consistent braking. A cooler rotor holds its bite and keeps the pedal feel firm.\u003c\/p\u003e\n\u003cp\u003eThe casting is one-piece gray cast iron. One-piece means the hat and the friction ring are a single casting, so there's no separate hardware to loosen or corrode between the two. Gray cast iron is the standard material for brake rotors for good reason: it damps vibration well, it machines cleanly, and it handles thermal cycling day after day. Hella finishes the non-friction areas with a zinc coating, which is the gray you'll see on the hat and edges. That coating fights the surface rust that blooms on bare cast iron the first time it gets wet, so the rotor looks clean behind an open wheel and stays that way longer.\u003c\/p\u003e\n\u003cp\u003eA few install notes from people who've done this a hundred times. Replace rotors in pairs, both sides of the same axle, even if only one looks worn. Braking is a balance act left to right, and a fresh rotor on one side with a tired one on the other pulls the vehicle under hard braking. Fit new pads at the same time. New pads on an old glazed rotor, or old pads on a fresh rotor, never seat properly and you lose braking performance you paid for. And once everything's bolted up, bed the pads in: a series of moderate stops from moderate speed that lays an even transfer layer of pad material onto the rotor face. Skip that step and you can end up with uneven deposits and a pulsing pedal.\u003c\/p\u003e\n\u003cp\u003eBecause this rotor ships as a single, order two if you're doing a full axle, which is the right way to do it. Keep the box until you've confirmed fitment on the car. If the numbers match your application, this is a straightforward, durable replacement that'll give you clean, quiet, predictable braking for a long time.\u003c\/p\u003e\n\u003c\/div\u003e\n\n\u003ch2\u003eKey Features\u003c\/h2\u003e\n\u003cul class=\"nvn-features\"\u003e\n  \u003cli\u003eVented rotor design with internal cooling vanes pulls heat out as the wheel spins, so the rotor sheds temperature faster and resists fade\u003c\/li\u003e\n  \u003cli\u003e320 mm (roughly 12.6 in) outside diameter gives a large swept area for strong, predictable stopping power\u003c\/li\u003e\n  \u003cli\u003e28 mm nominal thickness leaves plenty of material to wear down to the discard spec over a full service life\u003c\/li\u003e\n  \u003cli\u003e6 x 112 mm six-lug wheel bolt pattern, match it to your hub before ordering\u003c\/li\u003e\n  \u003cli\u003e68 mm center bore (hub size) seats the rotor square on the hub for true, vibration-free running\u003c\/li\u003e\n  \u003cli\u003eOne-piece gray cast iron casting keeps the hat and friction ring as a single part, with no separate hardware to loosen or corrode\u003c\/li\u003e\n  \u003cli\u003eZinc coating on the non-friction surfaces holds off surface rust so the rotor stays clean behind an open wheel\u003c\/li\u003e\n  \u003cli\u003eSold individually as a single rotor, order two to do both sides of an axle\u003c\/li\u003e\n  \u003cli\u003eHella part number 355123122 for a clean cross-reference against your vehicle's application\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cdiv class=\"nvn-trust\"\u003e\n  \u003ch2\u003eWhy Buy from NVN Marine\u003c\/h2\u003e\n  \u003cul\u003e\n    \u003cli\u003eAuthorized Hella Marine reseller, full manufacturer warranty\u003c\/li\u003e\n    \u003cli\u003eNMEA member and ABYC certified, advice from real boat techs\u003c\/li\u003e\n    \u003cli\u003eSame-day shipping before 3 PM ET on in-stock items\u003c\/li\u003e\n    \u003cli\u003eNY headquarters and Fort Lauderdale flagship retail store\u003c\/li\u003e\n  \u003c\/ul\u003e\n\u003c\/div\u003e\n\n\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\n\u003cdiv class=\"nvn-faq\"\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eWhat are the dimensions of this rotor?\u003c\/summary\u003e\n    \u003cp\u003eIt's 320 mm across the outside diameter with a 28 mm nominal thickness, a 68 mm hub size (center bore), and a 6 x 112 mm wheel bolt pattern.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eIs this a vented or a solid rotor?\u003c\/summary\u003e\n    \u003cp\u003eIt's a vented rotor. Internal cooling vanes are cast between the two friction faces to pull heat out as the wheel turns, which helps resist brake fade under load.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eDoes this come as a pair or a single rotor?\u003c\/summary\u003e\n    \u003cp\u003eIt's sold as a single rotor. If you're replacing both sides of an axle, order two so the braking stays balanced left to right.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eWhat is the wheel bolt pattern?\u003c\/summary\u003e\n    \u003cp\u003e6 x 112 mm, a six-lug pattern on a 112 mm circle. Confirm it matches your vehicle before ordering, along with the 320 mm diameter, 28 mm thickness, and 68 mm hub bore.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eWhat is the rotor made of?\u003c\/summary\u003e\n    \u003cp\u003eOne-piece gray cast iron with a zinc coating on the non-friction surfaces. Gray cast iron damps vibration and handles heat well, and the zinc finish fights surface rust.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eWhat does the zinc coating do?\u003c\/summary\u003e\n    \u003cp\u003eIt protects the hat and edges, the non-friction areas, from the surface rust that quickly forms on bare cast iron once it gets wet. The rotor stays cleaner looking behind an open wheel.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eShould I replace rotors in pairs?\u003c\/summary\u003e\n    \u003cp\u003eYes. Replace both rotors on the same axle at once, even if only one looks worn, so braking stays even side to side and the vehicle doesn't pull under hard stops.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eDo I need new brake pads too?\u003c\/summary\u003e\n    \u003cp\u003eIt's best to fit fresh pads with new rotors. Old glazed pads won't seat properly on a new rotor. After install, bed the pads in with a series of moderate stops to lay down an even transfer layer.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eWhat is the hub size or center bore?\u003c\/summary\u003e\n    \u003cp\u003eThe center bore is 68 mm. That's the machined opening that slides over your hub and locates the rotor so it runs true.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eHow do I confirm this fits my vehicle?\u003c\/summary\u003e\n    \u003cp\u003eMatch Hella part number 355123122 to your application and check the four key numbers against your current rotor: 320 mm diameter, 28 mm thickness, 68 mm hub bore, and the 6 x 112 mm bolt pattern.\u003c\/p\u003e\n  \u003c\/details\u003e\n\u003c\/div\u003e\n\n\u003ch2\u003eTechnical Specifications\u003c\/h2\u003e\n\u003ctable class=\"nvn-specs\"\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n\u003cth\u003eTitle\u003c\/th\u003e\n\u003ctd\u003eHella 355123122 Vented Disc Brake Rotor\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth\u003eBrand\u003c\/th\u003e\n\u003ctd\u003eHella\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth\u003eManufacturer Part Number\u003c\/th\u003e\n\u003ctd\u003e355123122\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth\u003eUPC\u003c\/th\u003e\n\u003ctd\u003e4082300574630\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth\u003eProduct Type\u003c\/th\u003e\n\u003ctd\u003eDisc Brake Rotor\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth\u003eRotor Design\u003c\/th\u003e\n\u003ctd\u003eVented\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth\u003eConstruction\u003c\/th\u003e\n\u003ctd\u003eOne-Piece\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth\u003eOutside Diameter\u003c\/th\u003e\n\u003ctd\u003e320 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth\u003eNominal Thickness\u003c\/th\u003e\n\u003ctd\u003e28 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth\u003eHub Size (Center Bore)\u003c\/th\u003e\n\u003ctd\u003e68 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth\u003eWheel Bolt Pattern\u003c\/th\u003e\n\u003ctd\u003e6 x 112 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth\u003eMaterial\u003c\/th\u003e\n\u003ctd\u003eZinc-Coated Gray Cast Iron\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth\u003eSold As\u003c\/th\u003e\n\u003ctd\u003eSingle\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003cscript type=\"application\/ld+json\"\u003e\n{\n    \"@context\": \"https:\/\/schema.org\",\n    \"@type\": \"FAQPage\",\n    \"mainEntity\": [\n        {\n            \"@type\": \"Question\",\n            \"name\": \"What are the dimensions of this rotor?\",\n            \"acceptedAnswer\": {\n                \"@type\": \"Answer\",\n                \"text\": \"It's 320 mm across the outside diameter with a 28 mm nominal thickness, a 68 mm hub size (center bore), and a 6 x 112 mm wheel bolt pattern.\"\n            }\n        },\n        {\n            \"@type\": \"Question\",\n            \"name\": \"Is this a vented or a solid rotor?\",\n            \"acceptedAnswer\": {\n                \"@type\": \"Answer\",\n                \"text\": \"It's a vented rotor. Internal cooling vanes are cast between the two friction faces to pull heat out as the wheel turns, which helps resist brake fade under load.\"\n            }\n        },\n        {\n            \"@type\": \"Question\",\n            \"name\": \"Does this come as a pair or a single rotor?\",\n            \"acceptedAnswer\": {\n                \"@type\": \"Answer\",\n                \"text\": \"It's sold as a single rotor. If you're replacing both sides of an axle, order two so the braking stays balanced left to right.\"\n            }\n        },\n        {\n            \"@type\": \"Question\",\n            \"name\": \"What is the wheel bolt pattern?\",\n            \"acceptedAnswer\": {\n                \"@type\": \"Answer\",\n                \"text\": \"6 x 112 mm, a six-lug pattern on a 112 mm circle. Confirm it matches your vehicle before ordering, along with the 320 mm diameter, 28 mm thickness, and 68 mm hub bore.\"\n            }\n        },\n        {\n            \"@type\": \"Question\",\n            \"name\": \"What is the rotor made of?\",\n            \"acceptedAnswer\": {\n                \"@type\": \"Answer\",\n                \"text\": \"One-piece gray cast iron with a zinc coating on the non-friction surfaces. Gray cast iron damps vibration and handles heat well, and the zinc finish fights surface rust.\"\n            }\n        },\n        {\n            \"@type\": \"Question\",\n            \"name\": \"What does the zinc coating do?\",\n            \"acceptedAnswer\": {\n                \"@type\": \"Answer\",\n                \"text\": \"It protects the hat and edges, the non-friction areas, from the surface rust that quickly forms on bare cast iron once it gets wet. The rotor stays cleaner looking behind an open wheel.\"\n            }\n        },\n        {\n            \"@type\": \"Question\",\n            \"name\": \"Should I replace rotors in pairs?\",\n            \"acceptedAnswer\": {\n                \"@type\": \"Answer\",\n                \"text\": \"Yes. Replace both rotors on the same axle at once, even if only one looks worn, so braking stays even side to side and the vehicle doesn't pull under hard stops.\"\n            }\n        },\n        {\n            \"@type\": \"Question\",\n            \"name\": \"Do I need new brake pads too?\",\n            \"acceptedAnswer\": {\n                \"@type\": \"Answer\",\n                \"text\": \"It's best to fit fresh pads with new rotors. Old glazed pads won't seat properly on a new rotor. After install, bed the pads in with a series of moderate stops to lay down an even transfer layer.\"\n            }\n        },\n        {\n            \"@type\": \"Question\",\n            \"name\": \"What is the hub size or center bore?\",\n            \"acceptedAnswer\": {\n                \"@type\": \"Answer\",\n                \"text\": \"The center bore is 68 mm. That's the machined opening that slides over your hub and locates the rotor so it runs true.\"\n            }\n        },\n        {\n            \"@type\": \"Question\",\n            \"name\": \"How do I confirm this fits my vehicle?\",\n            \"acceptedAnswer\": {\n                \"@type\": \"Answer\",\n                \"text\": \"Match Hella part number 355123122 to your application and check the four key numbers against your current rotor: 320 mm diameter, 28 mm thickness, 68 mm hub bore, and the 6 x 112 mm bolt pattern.\"\n            }\n        }\n    ]\n}\n\u003c\/script\u003e\n","brand":"Hella","offers":[{"title":"Default Title","offer_id":45060367908957,"sku":"2008491","price":109.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0299\/7266\/0317\/files\/ImageServerAPI_91ccbdfa-8550-4c45-86ff-4105793483d5.jpg?v=1789526987","url":"https:\/\/nvnmarine.com\/products\/hella-355123122-vented-brake-rotor-320mm-6x112","provider":"NVN Marine","version":"1.0","type":"link"}