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(1) Multipurpose Neoprene Rubber Sheet, 6" x 6", 1/4" thick, Durometer 40A (medium-soft) https://www.mcmaster.com/#1370n17/=1ccrr8u
(102 ropes, each 10-ft length) Ultra-flexible 18-8 Stainless Steel Wire Rope, 1/16" https://www.mcmaster.com/#3461t633/=1ccrtj3
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(15) 8-mm steel bearings (what we have used for slider - crank project)
(1 pack) 1.5" Long, 1/2" Diameter Compression Spring https://www.mcmaster.com/#9657k352/=1cjgoaf