4 Wheel Trolley Assembly Roller Trolley - Silent M10 Bolt and Nuts - Use with 1-5/8" Wide Wide and All 1-5/8" Unistrut Strut Channel (8 Set). High-Quality Material: Solid steel middle support - Channel Trolley body Rust-resistant galvanized surface, Eye nut and M10 bolt are made of stainless steel - Smooth and silent operation.
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