Customer Service: (800) 268-2141 (M-F 7AM to 5PM)
Customer Service: (800) 268-2141
(M-F 7AM to 5PM)  Contact || Help
Ascension group logo
wesspur youtube logo
wesspur instagram logo
Facebook logo
wesspur newsletter icon
Free Catalog of Tree Climbing Supplies and more
Free shipping on tree gear
Your shopping cart: Items, Total   View Cart or Checkout

Arborist Blocks

Arborist blocks are a very different piece of hardware than your standard pulley. An arborist block is the only appropriate choice for dynamic rigging where the load may fall and exert a shock-load upon the tree rigging system. An arborist block provides a better bend radius and more protection for the tree rigging line due to wide side plates. The upper sheave of an arborist rigging block accommodates a tree rigging sling. A true arborist block is an essential part of any tree rigging system, especially where negative-blocking or butt-hitching is concerned.

ISC Compact 1/2” Rigging Block

ISC Compact 1/2” Rigging Block

1/2" Compact Block
PUL153
1/2” Block & 1/2” x 4’ Loopie Sling
PUL153S

At approximately half the size of the standard small rigging pulley and weighing in at only 1 lb, the new Compact Rigging Pulley offers a highly impressive strength to weight ratio with an 85kN (19 000 lb) MBS and a WLL of 17kN (3,800 lb.) Can be used with rigging slings up to 5/8", and runs 1/2" tree rigging rope.

19,000 lb MBS, Manufacturer WLL 3,800 lb. Weighs 1 lb. ISC Part RP048

Review this item Read reviews

1/2” Capacity Aluminum Spring Block

ISC Small 1/2" Arborist Spring Block

1/2” Block
pul146
1/2” Block & 1/2” x 4’ Loopie Sling
pul146s

A tough, sleek, and well-engineered arborist block for 1/2” lines. ISC spring blocks are among the best rigging blocks in the world, and this little workhorse brings their great design to bear for 1/2” tree rigging lines.

22,480 lb MBS, Manufacturer WLL 4,400 lb. Weighs 3 lb 6 oz. ISC Part RP050

Review this item

5/8” Capacity Aluminum Spring Block

ISC Small 5/8" Arborist Spring Block

5/8” Block
pul213
5/8” Block & 5/8” x 6’ Loopie Sling
pul213s

This spring block is one of our most popular arborist blocks. The design is compact and the unique upper sheave design is quick to open & close and secures easily, plus it eliminates the chance of dropping a sheave. The side plates are thick aluminum, powder-coated to enhance the durable life of the block. Strong and durable.

22,480 lb MBS, Manufacturer WLL 4,496 lb. Weighs 3 lb 4 oz. ISC Part RP051

Review this item

5/8” Capacity Aluminum Spring Block

ISC Medium 5/8" Arborist Spring Block

5/8” Block
pul217
5/8” Block & 5/8” x 6’ Loopie Sling
pul217s

ISC 5/8” spring block in the "medium" style steps up the strength and working load. The rope-friendly edges, large sheave, and retained upper sheave which opens quickly with the twist and push pin are the same as on our popular small ISC block above, but with beefed up strength.

33,720 lb MBS, Manufacturer WLL 6,600 lb. Weighs 4 lb 9 oz. ISC Part RP054

Review this item

ISC Medium 3/4" Arborist Spring Block

3/4” Block
pul303
3/4” Block & 3/4” x 8’ Loopie
pul303s

This spring block is one of our most popular large arborist blocks. The design is compact and the unique upper sheave design is quick to open & close and secures easily, plus it eliminates the chance of dropping a sheave. The side plates are thick aluminum, powder-coated to enhance the durable life of the block. Strong and durable.

33,000 lb MBS. Weighs 4 lb 14 oz. ISC Part RP055

Video product overview of the ISC Arborist Spring Block by Niceguydave.

Review this item Read reviews

ISC Large 3/4" Arborist Spring Block

3/4” Block
pul304
3/4” Block & 3/4” x 8’ Loopie
pul304s

ISC's large 3/4" block has the same sleek design and captive upper bushing as ISC's other blocks with an oversized lower sheave and excellent strength.

45,000 lb MBS. Weighs 7 lb 10 oz. ISC Part RP057

Video product overview of the ISC Arborist Spring Block by Niceguydave.

Review this item

3/4” CMI Steel Arborist Block

3/4” Block
pul306
3/4” Block & 3/4” x 8’ Loopie Sling
pul306s

An affordable and rugged zinc-plated steel arborist block from CMI. Steel body, swinging side plates, and fixed upper sheave. Affordability and durable design make this a great value.

Note: With this style of block, care must be taken that the relatively sharp side plates do not contact the rope.

25,000 lb MBS. Weighs 3 lb 10 oz.

Video Overview by Niceguydave.

Review this item

CMI 5/8” Stainless Steel Arborist Rigging Block

CMI Stainless Steel Arborist Blocks

5/8” Block
pul215
5/8” Block & 5/8” x 6’ Loopie Sling
pul215s

This best selling Arborist Block features a wide upper bushing to maximize sling strength and wide side plates to protect the rope from abrasion. One-piece design eliminates lost parts. 3” lower sheave will accept bull ropes up to 5/8” diameter. Stainless steel side plates, aluminum bushing, and zinc-plated steel axle means this pulley stands up to the elements as well as the load.

Note: With this style of block, care must be taken that the relatively sharp side plates do not contact the rope.

28,000 lb MBS, Manufacturer WLL 4,000 lb. Weighs 2 lb 5 oz.

Review this item

CMI 3/4” Stainless Steel Arborist Block

CMI 3/4” Stainless Steel Arborist Block

3/4” Block
pul302
3/4” Block & 3/4” x 8’ Loopie Sling
pul302s

This larger version of the best-selling stainless steel arborist block from CMI accommodates tree rigging ropes up to 3/4” in diameter and features increased strength.

Note: With this style of block, care must be taken that the relatively sharp side plates do not contact the rope.

40,000 lb, MBS, Manufacturer WLL: 6,000 lb. Weighs 5 lb 10 oz.

Review this item

CMI 3/4” Aluminum Arborist Block

CMI 3/4” Aluminum Arborist Block New in 2017!

pul309

CMI's compact aluminum block is small and strong with a large capacity and robust design. Knurled knob for easy push and turn opening. Orange 7075 alloy sideplates, 3-inch aluminum sheave, bronze bushing and stainless steel axle. Proudly made and manufactured in the USA.

51,000 lb MBS. Weighs 2 lb 15 oz.

Review this item

1” Aluminum Arborist Block

1” Block
PUL402
1” Block & 3/4” x 8’ Loopie
PUL402s

Finally, a bigger arborist block is available at better price. CMI has made a great oversized aluminum block with a maximum capacity of 1” and an impressive MBS of 68,000 lb. and manufacturer working load limit of 13,600 lb - over 6 tons. For years the only 1” we could offer cost almost $500. The 1” arborist block allows you to run your biggest ropes through hardware that can handle similarly big loads. This block from the makers of our bestselling stainless steel arborist block is a big 9.25” x 6” yet weighs in at only 6.6 lb.

The block swings open yet the upper sheave is retained so there is no risk of losing it while installing your sling, and you can fit up to a 1” sling for really big jobs. The lower sheave will give you a proper bend radius for 3/4” and larger rope (though it is a bit tight on 1”). The block features anodized aluminum sideplates, an aluminum sheave, bushing, and stainless steel axle.

68,000 lb MBS. Weighs 6 lb 10 oz.

Review this item

DMM Impact Blocks

DMM 5/8" Impact Block

5/8” Block
pul216
5/8” Block & 5/8” x 6’ Loopie Sling
pul216s

DMM's new blocks are designed specifically for the high-impacts of tree rigging & removal. The combination of high quality materials and advanced production processes has ensured a rope friendly, durable and robust product. During design each Impact Block has gone through a thorough dynamic and static testing regime, the end result is a highly functional product with an impressive strength to weight ratio.

45,000 lb MBS. Weighs 4 lb.

Review this item

DMM 3/4" Impact Block

3/4” Block
pul308
3/4” Block and 3/4” x 8’ Loopie Sling
pul308s

The 3/4” DMM Impact Block is unparalleled in strength and quality of design. The block is designed to be rope-friendly on all surfaces and accommodates 3/4” rigging ropes on a wide sheave. The large DMM Impact Block is an investment in the ultimate in strength and function.

67,500 lb MBS. Weighs 7 lb 10 oz.

Video product overview of the DMM Impact Block by Niceguydave.

Review this item

Contents of this site are copyright 2010 by WesSpur Tree Equipment, and may not be used without written permission.