125mm Aluminum Stand-up Block

Part No. 3261

Sheave Ø (mm) 125 mm

Sheave Ø (in) 4 15/16 in

Maximum line Ø (mm) 19 mm

Maximum line Ø (in) 3/4 in

Maximum working load (kg) 4990 kg

Maximum working load (lb) 11000 lb

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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. Sideplates and sheaves Hard Lube-anodized for maximum UV protection and a smooth surface. Center cage keeps Torlon® roller bearings separated and parallel to reduce friction. Torlon is a registered trademark of Solvay Advanced Polymers L.L.C.

Specifications Resources Spare Parts

Sheave Ø (mm)	125 mm
Sheave Ø (in)	4 15/16 in
Length (mm)	230 mm
Length (in)	9 1/16 in
Width (mm)	127.5 mm
Width (in)	5 1/32 in
Weight (g)	1268 g
Weight (oz)	44.72 oz
Maximum line Ø (mm)	19 mm
Maximum line Ø (in)	3/4 in
Maximum working load (kg)	4990 kg
Maximum working load (lb)	11000 lb
Breaking load (lb)	22000 lb
Breaking load (kg)	9979 kg
A (mm)	93 mm
A (in)	3 21/32 in
B (mm)	106 mm
B (in)	4 3/16 in
Footnote	Uses hole spacing and base dimensions of 648 padeye. Maximum working load decreases at varying angles.
Includes	Includes padeye. Uses hole spacing and base dimensions of 648 padeye. Maximum working load decreases at varying angles.
C (mm)	57 mm
C (in)	2 1/4 in

3D drawing - IGS 3261.IGS.zip 1.46 MB Photo - EPS 3261.eps.zip 1.18 MB Photo - JPG 3261.jpg 0.09 MB Drawing - DXF 3261.DXF.zip 0.09 MB Drawing - DWG 3261.DWG.zip 0.09 MB

ID BOM	Qty		Price
H-34392B	1	more info
Sheave Assembly - 125 mm Black Magic Block Sheaves are Hard Lube-anodized for maximum UV protection and a smooth surface. Captive Delrin ball bearings carry side loads.
HFS1272	1	more info
Fastener - M6 1 x 10mm Socket Head Shoulder Screw Cup, Black Set screw allows shackle to be fixed or to swivel.
MP-3037	2	more info	$1.65	Add to cart
Headpost Collar Half - 100/125 mm Black Magic Block Headpost collar isolates dissimilar metals to prevent corrosion. Collar accepts set screw that fixes shackle in one direction or allows it to swivel.
MP-1865	1	more info	$23.55	Add to cart
Stand-up Base - 100/125 mm Block Made of durable, flexible rubber, the stand-up boot holds block upright without snagging lines.
HBB88ASSY	1	more info
Roller Cage Assembly - 125 mm Black Magic Block Center cage keeps Torlon® roller bearings separated and parallel to reduce friction.
HFS1275	3	more info	$2.00	Add to cart
Fastener - M8 x 1.25 x 16 mm Socket Head Cap Screw, Black Fasten with M8 hex wrench.
AL-3771	1	more info	$192.60	Add to cart
Sideplate with Helicoils - 125 mm Black Magic Block Sideplates are Hard Lube-anodized for maximum UV protection and a smooth surface.
AL-3772	1	more info	$192.60	Add to cart
Sideplate with Isolators - 125 mm Black Magic Block Sideplates are Hard Lube-anodized for maximum UV protection and a smooth surface. Dissimilar metals are isolated to prevent corrosion.
MS-3018	1	more info	$347.75	Add to cart
Padeye Assembly with Head Post - 100/125 mm Block 17-4 PH stainless steel padeye base. Use 10 mm (3/8") fasteners.