These blocks from DMM are the result of a 3-year project in consultation with Treemagineers to produce a tailboard rigging block second to none on earth. Starting from a clean slate, Treemagineers (designers of the Treemotion saddle) listed every advantage and disadvantage known about current tailboard block designs and set out to improve them. Two things needed most were increased strength and more rope-friendly interaction between the cheekplates, bushings, and sheaves. Like Treemagineer's popular Hitch Climber Pulley, no prefabricated bolts, pins, or plating were welcome in the design process. All componentry was to be forged or CNC-milled specifically for the finished product. All edges had to be smooth, and connecting points either countersunk or rounded to a sexy, fabric-friendly finish. And this is exactly what you'll receive with your impact pulley investment. Hot-forged from 6082-T6 aluminum alloy for maximum strength-to weight ratio, then polished, heat-treated, and anodized for an incredibly robust finish, the chassis of this compact dynamo has proven in extensive testing to withstand unparalleled punishment and abuse. Both the stainless-steel 303 spindle and anchor pins holding sheave and bushing have beefy, self-lubricating Oilite bronze bushings for years of trusted service life. Initial testing of early prototypes demonstrated without doubt that DMM's design and understanding of metallurgy were spot-on. With only a few minor tweaks, the final product has proven stronger than even steelbodied blocks of considerably higher weight! Whether you're seeking premium-grade hardware to please your euc man tendencies or bulletproof design for your oak man side, consider an investment in the new impact block for technical rigging your best decision of the millennium!