Pololu Wheel 80x10mm Pair - Black These black plastic wheels press fit onto the 3mm D shafts of our mini and micro metal gearmotors to make a nice drive solution for small robots.
Wheel 32x7mm Pair - White
Wheel 32x7mm Pair - Black
Ball Caster Plastic - 3/8"
Wheel 90x10mm Pair - Black
Ball Caster Metal - 3/8" This ball caster kit from Pololu includes a black ABS housing, a 3/8" diameter metal ball, two spacers (1/16" and 1/8" thick), and two #2 screw sets.