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Classic Blocks Q&A

What is the difference between the 3.00" blocks and 3.00" Midrange blocks?
Although these blocks both have the same diameter sheave, the Midrange block has a much higher Maximum Working Load (MWL). We increased the Midrange block's MWL by using a forged shackle, a larger diameter shackle pin with a higher shear value, and stainless steel straps on sideplates that wrap over the top of the block.

What is the difference between the Midrange 3.00" blocks and the ESP style blocks?
The Midrange and ESP 3.00" blocks have different Maximum Working Loads (MWL). The ESP block can handle higher loads because it uses a stainless steel journal type bearing instead of ball bearings to handle axial loads. It also has aluminum sideplates. However, with an escalating MWL ,there's also more friction. An ESP block is usually used to change the direction of a statically loaded line.

The lesson is that all like-sized blocks are not the same. Before choosing a block you must determine the load the block will be under to find the right one for a given use.

How do I lock the headpost into position on my 2.50", 3.00" and Midrange blocks?
To lock the headpost in the front or side position, loosen the two screws in the sideplate (right under the headpost). Turn the block to the desired position, and tighten the screws.

Can I use the same block for wire rope and synthetic line?
In many cases you can use synthetic line in a wire rope block because the aluminum sheave works well with braided rope.

Can I use wire rope in a standard block?
Never use wire rope in a standard block. Most standard blocks have plastic sheaves that will not hold up to the steel in wire rope. 

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