Stainless-steel wheel with ball bearings, four wheels are made of solid Teflon. The pulley wheel is also made of stainless steel, it has 3 wheels in individual housings to prevent derailing & increases pull down height.
Triangle for the strap to pass through is also stainless steel, it has a sleeve on the bottom shaft for smooth rolling and has a 3mm slit to allow the strap to be easily inserted.