29mm Carbo Clew Block Assembly from HARKEN
From the folks who invented ball bearing blocks, this line of blocks boasts an excellent strength-to-weight ratio. 29mm doubles and triples feature a U-lock to hold the swivel in the front or side position, or allow it to spin freely. Use the 40mm blocks for jib and mainsheet systems on high-performance dinghies, and for high-load control lines on small keelboats. The 57mm blocks have an enormous working range that makes them ideal for main and jib sheets, spinnaker halyards and control lines.

Series 40 Ratchet Block, Single/Cleat, 385lb. SWL, 3.4oz. from RONSTAN
Practical Sailor's Ratchet Block Click-Off rated Ronstan's Orbit block "Overall, the most impressive with its grip, versatility, and lightweight design. " The newest addition to Ronstan’s Orbit range of super lightweight, fiber-reinforced blocks. Ideal for sheet applications on dinghies up to 16' and control line applications for small keel boats. There are two styles of Series 40 ratchet blocks. Many of the top Grand Prix Laser sailors are switching to Orbit blocks.

Ratchet Orbit Block, Cheek, Counter-Clockwise, 550lb. SWL, 2.7oz. from RONSTAN
Practical Sailor's Ratchet Block Click-Off rated Ronstan's Orbit block "Overall, the most impressive with its grip, versatility, and lightweight design. It can be set at a 0 or 90 degree orientation, provides stress-free articulation without allowing the block to over-rotate, and is locked in place with a security clip that doesn’t require tools to fit. The Dyneema link is also more compatible with carbon, Dyneema and webbing connection points than steel loop tops or shackles.

Delrin Sheave, 1/2" Max. Line Dia., 1-7/16" OD, 3/8" ID, 5/8" Width from SCHAEFER
Schaefer sheaves are designed to be compatible with Schaefer products, and are not intended for use in other manufacturer's blocks. Delrin sheaves are injection molded with UV inhibitors and monitored molding cycles for a stronger product.

60mm Racing Fiddle Block with Becket & Cleat, 882lb. SWL, 12.4oz. from LEWMAR
For chafe-free, low-friction tackles. Sheave: Anodized aluminum alloy . Ball Bearings: Delrin® . Sheave Size: 2-3/8" (60mm) & 1-5/8" (40mm) . Line Dia. : 3/8" max. . Cheek Material/Finish: Anodized aluminum alloy . Shackle/Strap Type: Swivel with three-way locking, drilled-out head . Cleat: Model with cleat: adjustable arm, aluminum cam cleat .

57mm Black Magic AirBlock, High-Load Strap Head with Becket, 2,500lb. SWL, 3.6oz. from HARKEN
Strong, lightweight aluminum blocks for offshore boats Used for sheets, halyards, running backstays and control lines on offshore boats, these strong, lightweight blocks are made of sculpted aluminum with Torlon rollers and carbon black balls for strength and UV protection. Cheek Material/Finish: 6160-T6 Hardkote anodized aluminum . Sheave Size: 57mm (2-1/4") . Construction: Three fasteners for quick disassembly. Plastic isolators separate dissimilar metals. Three-way head system.