Barton Marine Size 0 20mm Plain Bearing Cheek Block (N00160)

The Barton Marine Size 0 cheek block is one of those small pieces of hardware that quietly does a lot of work on a boat. It's a single 20mm (3/4 inch) sheave running on a plain bearing, built into a low-profile body that screws flat against a surface. No shackle, no becket, no swivel. Just a clean, fixed turning point for your line wherever you need to redirect a load. Barton has been making these in Whitstable, England for years, and the Size 0 is the smallest and lightest block in their range, so it's the one you reach for when weight and space both matter.

What makes a cheek block different from a standard block is how it mounts. Instead of hanging from an eye or a shackle, it sits flush against a flat surface, a mast, a spar, a transom, or a cabin top, and takes its fixing screws straight through the body. That gives you a low-profile lead exactly where you fasten it. Dinghy sailors use these to route control lines tight to the deck, and on bigger boats they're handy as lead blocks for flag halyards, pennants, and light lines that don't need a floating block hanging off a padeye.

This version uses a plain bearing, which means the sheave turns on a smooth bushing rather than a race of ball bearings. For a cheek block that mostly redirects line under steady load, that's exactly what you want. It's simpler, it shrugs off side load, and there's less to wear out over the seasons. Barton also offers this same Size 0 body with a ball bearing sheave, so if you've got a high-cycle spot where the line runs constantly and you want the sheave to free-spin under lighter loads, you have that option in the same family. For most cheek-block jobs, though, the plain bearing is the sensible pick.

The numbers are honest for the size. The 20mm sheave takes line up to 6mm (1/4 inch), the safe working load is 275kg (606 lbs), and the breaking load is 550kg (1210 lbs). The whole block weighs just 17 grams. That strength-to-weight ratio is why these turn up on racing dinghies, day sailers, and small catamarans where every gram counts. It's a Size 0, so it's built for smaller craft and lighter lines. It's not the block for your primary sheet loads on a 30-footer, but for control lines and light leads it's spot on.

Install is straightforward, but it's worth doing right. On a solid spar or a thick deck you can screw it straight down. On a thin fiberglass hull or panel, back it up with a backing plate or at least some large washers so the fixing screws don't crack the gelcoat under load. Older boats sometimes have existing hardware holes that won't line up, so be ready to drill fresh pilot holes and seal them properly. And if the line is going to run at a sharp angle across the cheek plate, ease the plate edges a touch during install so they don't chafe the cover over time.

Maintenance is about as easy as it gets. If you sail in salt water, give it a freshwater rinse when you rinse down the rest of the boat. Plain bearings are happiest when they stay clean, and a quick rinse keeps salt from building up around the sheave. There's no lubrication schedule to fuss over and no ball races to flush out. Rinse it, check the fixing screws now and then, and it'll keep turning season after season.

So who's this for? If you're rigging a dinghy, a day boat, or a small multihull and you need a compact, screw-down turning point for line up to 6mm, this is a straight answer. It's also a smart, tidy choice as a lead block for flags, pennants, and light control lines on a larger yacht. If you're carrying heavy sheet loads or running line bigger than 6mm, step up to a larger Barton size. But for its job, the Size 0 cheek block is simple, strong, and light. That's exactly what you want from a small block.