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Mechanical Advantage sets for Arborists

Arborists spend a lot of time rigging loads down, but sometimes it's necessary to lift a limb or load. With these mechanical advantage system, you can generate a serious mechanical advantage in your favor, multiplying the force the user puts into the system. These kits can be used to lift fallen limbs, tension a speedline, or induce lean in trees. Some mech advantage kits contain a progress capture device in the upper pulley, or a rope grab or prusik in the system, so that the load won't slip even if you let go of the rope.

Aerial Rescue: A primary reason to carry a Set of 4s in your gear kit is for aerial rescue. If you need to bring a climber down from a tree, you may need to lift them off of their system before you can lower them. The Aztek is especially good for rescue, and the Petzl JAG is designed specifically for the task.

Advance Tech HX Mechanical Advantage Kit


Generate mechanical advantage with the Advance Tech HX pulley from SMC with built-in progress capture and quick release of the cam (even under tension). This compact system can be used in place of bulkier block and tackle sets due to the high strength of the SMC pulleys and SMC Twist Lock carabiners. A great system for quick mechanical advantage with built-in capture and smooth operation.

Contains: SMC Advance Tech pulley, 60' of 7/16" HTP rope, two SMC Twist Lock carabiners, quick link, and SMC Advance Tech Mate Pulley. Color of rope may vary.

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SMC Advance Tech HX Pulley


Double pulley with integrated cam that provides immediate progress capture without the need of prusik loops. Stainless pins retain the rope when a rigged system is packed so that system can be pulled out and used immediately. Manufactured from high quality aluminum and anodized to help prevent corrosion. Ideal for all rescue applications where a small mechanical advantage system is being utilized. Up to 1/2” capacity. 34kN / 7,650lb breaking strength (18 kN / 4,050 lb for the becket).

Check out our full Advance Tech Mechanical Advantage Kit.

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Aztek Elite System (Set of 4s)

Aztek Elite System
Pulley Set Only
Prusik (dark)
Prusik (light)
8mm x 50' Rope
Sterling Carry Bag

The AZTEK elite system utilizes sewn cord products to create a mechanical advantage system. System contains two AZTEK Omni pulleys, 2 x 6mm sewn ratchets, and 2 Sterling SafeD carabiners. The AZTEK is contained in a compact hip-carry pouch. Creates either a 5:1 mechanical advantage or a 4:1 with a change of direction. Applications include lifting downed limbs, rescue, and more.

Compact Set of 4s

Compact Set of 4s


This compact set of 4s can be stowed anywhere and brought out when you need some additional power. Uses 8mm Sterling cord running on SMC Jigger Rescue Pulleys, with a bound prusik loop for progress capture. 700 lb WLL.

Contains 2 x SMC Jigger Rescue Becket Pulleys, 1/4 Quick Link, 2 x DMM Phantom Screwgate, 40' Prusik 8mm cord w/ Sewn Eye, 6mm x 12" Bound Loop Prusik.

Petzl JAG System - Haul Kit for Pickoffs

Petzl JAG System - Haul Kit for Pick-offs

JAG System (complete)
JAG Pulley Only
JAG Traxion Only

Petzl's JAG kit is ideal for aerial rescue kits. This haul kit is great for pick-offs, making a releasable anchor, or tensioning a system, thanks to its 4:1 mechanical advantage and excellent efficiency (sheaves with sealed ball bearings). The collapsed kit is very compact, making usage possible even if the distance to the anchor is very short - especially useful for lifting an injured climber if there is very little room to anchor the kit. The JAG system haul kit is quick and easy to deploy: it is ready to use thanks to the flexible cover that prevents any risk of tangling. The haul end is color coded for instant identification.

The Jag Pulley and progress-capturing Jag Traxion are also available individually for building your own set of 4s.

Petzl Jag System Video

SMC Large (3”) Set of 4s

SMC Large (3”) Set of 4s

w/ 100' of Rope
rig502 Built to order

Large set of 4's built around SMC 3” prusik minding pulley's and 1/2” Samson stable braid.

    Kit Contains:
  • SMC 3" Double NFPA Pulley (PUL145) x 2
  • 1/2" Maillon Rapide Quick Link (HAR130)
  • SMC ANSI FP Lite Alloy Twist Lock Carabiner (CAR501)
  • Tenex 10mm (3/8") Rigging Prusik (RIG403)
  • 1/2" Stable Barid Rigging Rope x 100' (SB12B)
  • Hand-spliced Eye in Stable Braid
  • Small Rope Bag
Piggyback / Z-Rig Kit

Piggyback / Z-Rig Kit


Essential components for a creating a 3:1 Z-Rig or 4:1 Piggy Back with progress capture on 1/2" line. Contains 2 x RockO Auto Lock Carabiners, 2 SMC Micro PMP Pulleys, and 2 Sterling RIT Bound Loop Prusiks.

3/8” Tenex Rigging Prusik

Rigging Prusik

3/8” x 36” Prusik
3/8” x 18” Loop
1/2” x 36” Prusik

Made from Tenex single-end carrier, 1/2” and 3/8” diameters with sewn eyes. 36” length is longer than standard for extra wraps on large diameter ropes.

Not for use on your climbing line.

5:1 Fiddle Blocks

5:1 Fiddle Blocks


Get more power for your work with this 4 pulley system. Upper block has integrated cam device to hold forward progress of rope. Can be used to help you get the most from your Port-a-Wrap. The mechanical advantage you generate with this set will help lift and lower the heaviest of loads. Replacement parts available.

Blocks have 1,000 lb WLL • Works with all 1/2” lines • Generates a 5:1 mechanical advantage.

Block and Tackle Sets

Block and Tackle Sets with Predator Rope

Set w/50’ Rope
Set w/75’ Rope
Set w/100’ Rope

These block and tackle sets combine the fiddle blocks with pre-sewn Samson Predator ropes for a handy mechanical advantage system. Predator is a 1/2", 24-strand rope with an excellent camo pattern and great handling.

CMI Rope Jack


The CMI Rope Jack is a Mechanical Advantage tool for pre-tensioning static lines, light lifting and cabling. The Rope Jack is small enough and light enough to be carried aloft by a climber for Mechanical Advantage within the crown. The length of the handle on the Rope Jack limits excessive loading to avoid rope damage.

Under no circumstances should a cheater bar be used to increase leverage as it may damage the unit, the rope, or severely injure personnel. It is designed to be used by only one individual using one hand only; it shall be removed before any 'shock' load is applied; it shall NOT be used for heavy or dynamic loads as there are other tools available for those applications. It can attach mid-line and can run virtually any length of rope. The MA is approximately 5:1 - no pulleys, no extra rope, minimum weight, minimum friction, quick, easy on-off, works well 'topside', too. The CMI Rope Jack is used to remove slack & stretch for lowering and to lift the tips on light limbs without having to break out the big guns. It is NOT for heavy loads. Cams, even 'untoothed' like a Rescucender and Gibbs, have been shown to shred a rope with high loading. There are much better tools for the heavy work.

The rope jack is approved for life support use as long as another form of progress capture device is used in conjunction with the device. Never use the Rope Jack by itself for hauling human cargo. The CMI Rope Jack is approved for static ropes from 3/8-5/8" diameters. Testing has shown that a single person can generate somewhere between 300-80O pounds of force while using the Rope Jack. Testing revealed CMI ascenders will strip the sheath of brand new 1/2" rope at roughly 1500lbs). To remove a load from the Rope Jack, pull the handle and allow the trailing cam to loosen, then pull handle again and allow the forward cam to loosen. Releasing the Rope Jack will take a little practice. The Rope Jack should be relieved from tension a little bit at a time off each cam.

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CMI Uplift Pulleys

Uplift Kit w/ 300' HTP
pul170k3 Built To Order
Uplift Kit w/ 200' HTP
pul170k2 Built To Order
Uplift Unit Only
Uplift Pulley Only
Uplift Pulley w/ Becket Only
pul170‑b Ships from CMI

Four-to-one mechanical advantage system from CMI, with a remote release feature.

Kit Contains: Uplift Unit (PUL170), Uplift Pulley (PUL171), 2x SMC crossover triple lock carabiners (CAR146), and 200 or 300' 11mm Sterling HTP. Individual components also available.

A double pulley is mated to a remotely triggered retractable brake. When rigged with the matching color coded companion pulley it serves as the core of a simple four-to-one mechanical advantage system. Easy to set up, easy to store and easy to use, the entire system can be pre-rigged and stored for quick deployment.

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