Various Idlers for  20tooth or no tooth  6mm/10mm gears
Detail Description : 
GT2 Idler Timing Pulley 20 Tooth Wheel Bore 6/10mm Aluminium Gear Teeth Width 6mm/10mm

20T ID3 OD18 W6 -> 20teeth, Bore3mm, Outerdiameter18mm, Using for 6mm timing belt.
NTID5 OD18 W6 -> No teeth, Bore5mm, Outerdiameter18mm, Using for 6mm timing belt.
20T ID5 OD18 W6 -> 20teeth, Bore5mm, Outerdiameter18mm, Using for 6mm timing belt.
20T ID5 OD18 W10-> 20teeth, Bore5mm, Outerdiameter18mm, Using for 10mm timing belt.
20T ID6 OD16 W6-> 20teeth, Bore6mm, Outerdiameter16mm, Using for 6mm timing belt.