1pcs Od 50 Mm High Load Plastic Coated Bearing Rollers 10x50x12 Mm Bs620050-12 Pom 3d Printer Guide Wheel 10*50*12 Delrin Pulley - Bearings - AliExpress
Rowing Parts - Rowing Seat Wheels for rowing shells and coastal rowing shells — Rowing Parts Supply - Your headquarters for all rowing parts and rowing supplies
Seat Roller 45 mm, for sale at Helisports.
Plastic Rowing Machine Seat Wheels with S626 Bearing for Boat Rowing Seat Plastic Ball Bearing - China Deep Groove, Ball Bearing | Made-in-China.com