Our Speed-Wheels come with 8" swivel care-free (foam-filled) tires. 
The adapters are manufactured out of 1-5/8" (outside diameter) steel.  These adapters accommodate all fittings for 1-1/4" and 1-1/2" pipe.  These wheels are perfect for a quick Speed-Rail® rig that requires movement or for creating your own rickshaw or Speed-Rail® dolly.  The Speed-Wheels feature a strong and durable locking mechanism, ensuring ease of use.