0item in your cart

57 mm Aluminum Block — Swivel

57 mm Aluminum Block — Swivel

Part No. 3215

Sheave Ø (mm) 57 mm

Sheave Ø (in) 2 1/4 in

Maximum line Ø (mm) 12 mm

Maximum line Ø (in) 7/16 in

Maximum working load (kg) 1134 kg

Maximum working load (lb) 2500 lb

Black Magic Air blocks are a top favorite of Big Boat performance racers and cruisers. These lightweight, free-running, powerful performers are used for sail controls that see lots of action: mainsheet, runner, halyard, and spinnaker systems. A center cage keeps Torlon® roller bearings separated and parallel to reduce friction. Shackle blocks lock in two directions or swivel to keep line from twisting. Torlon is a registered trademark of Solvay Advanced Polymers L.L.C.
Sheave Ø (mm)57 mm
Sheave Ø (in)2 1/4 in
Length (mm)119 mm
Length (in)4 11/16 in
Weight (g)152 g
Weight (oz)5.36 oz
Shackle pin Ø (mm)6 mm
Shackle pin Ø (in)1/4 in
Maximum line Ø (mm)12 mm
Maximum line Ø (in)7/16 in
Maximum working load (kg)1134 kg
Maximum working load (lb)2500 lb
Breaking load (kg)2268 kg
Breaking load (lb)5000 lb
32152108SP-060MP-3030MP-3030AL-3702AL-3703H-34389AHBB85MP-3020MP-3020HFS796HFS796HFS798
ID BOM Qty Price
2108 1 more info $14.05 add to cart

6 mm "D" Shackle

Forged stainless steel shackles are polished to a high luster and are stamped with the screw pin diameter. "D" shackles are the most common type of shackle. They are best suited for aligned attachment points.

SP-060 1 more info $22.00 add to cart

Headpost - 57 mm Black Magic Single Block

Black Magic blocks have 17-4 PH stainless headposts.

HFS796 3 more info $0.30 add to cart

Fastener - M4 x .7 x 12mm Socket Head Cap Screw, Black

Fasten with M4 hex wrench.

MP-3020 3 more info $1.00 add to cart

Fastener Isolator - 4 mm SK HD

Dissimilar metals are isolated to prevent corrosion.

HFS798 1 more info $0.35 add to cart

Fastener - M4 0.7 x 8mm Stainless Steel Socket Head Shoulder Screw Cup, Black

Set screw allows shackle to be fixed or to swivel.

MP-3030 2 more info $1.50 add to cart

Headpost Collar Half - 57 mm Black Magic Single Block

Headpost collar isolates dissimilar metals to prevent corrosion. Collar accepts set screw that fixes shackle in one direction or allows it to swivel.

AL-3702 1 more info $54.00 add to cart

Sideplate with Helicoils - 57 mm Black Magic Block

Sideplates are Hard Lube-anodized for maximum UV protection and a smooth surface.

AL-3703 1 more info $54.00 add to cart

Sideplate - 57 mm Black Magic Block

Sideplates are Hard Lube-anodized for maximum UV protection and a smooth surface.

HBB85 1 more info $28.00 add to cart

Roller Cage Assembly - 57 mm Black Magic Block

Center cage keeps Torlon® roller bearings separated and parallel to reduce friction.

H-34389A 1 more info $26.21 add to cart

Sheave Assembly - 57 mm Black Magic Block

Sheaves are Hard Lube-anodized for maximum UV protection and a smooth surface. Captive Delrin® ball bearings carry side loads.