Diameter 50mm * thickness 1.5mm O belt roller driving pulley double O conveyor roller Spring Shaft|roller conveyor|belt driveconveyor belt rollers - AliExpress
Premium #50 O-Ring Roller Chain
Drive 'O' rings for live rollers | Brendma
WD Custom Roller Saddle Tune-O-Matic Bridge
Fixed roller Ø 36 mm without brake plastic wheel load capacity 50 kg, 661.05.320