Amazon.com: 4" Diameter X 1.7" Width Malleable V-Groove Wheel with Bolt & Nut, 1,000 lbs Capacity (1) : Tools & Home Improvement
Amazon.com: YATOINTO 2PC 4 Wheel Trolley Assembly, Stable Welded Roller Trolley Silent M10 Bolt for use with 1-5/8" Wide and All 1-5/8" or Taller Strut Channel : Industrial & Scientific
TOMUM Set of 6pcs CY-25D Bolt Type 1" Nylon Ball Transfer Bearing Unit Table Conveyor Roller Ball with Bolt for Transmission, Furniture, Wheelchair: Amazon.com: Industrial & Scientific
Body Bolt Vibrating Foam Roller – Electric Foam Back Roller with 4 speeds for Recovery – Deep Tissue, Trigger Point Sports Massage Therapy – High Intensity Muscle Roller : Amazon.co.uk: Sports & Outdoors