38mm diameter x 13mm wide silicone rubber wheels on narrower, internal set-screw hub
These are the big brother to the regular RW28x13 / RW2, for when you need more clearance and traction. It features a silicone rubber molded wheel on a lathe-machined aluminum hub.
The hub is narrower than the standard version, as the set-screw hole has been removed from the collar (which was then removed), and moved to the main part of the hub, under the wheel itself.
This makes for a narrower wheel for tighter installations. We've even found we can place the gearmotor gearhead in the hub cavity itself for very tight installations.
Secure it to your motor shaft with the included 4-40 hex grub/setscrew (requires 0.050 hex wrench, like our HexW050).