This is the same tyre found on the Qu-Ax Muni Starter model - but a bright, popping Green! Very chunky and made to Qu-Ax's normal high standards. inflatable up to a pressure of 50 PSI (3,5 bar) and capable of high rebounds. 20″x 2,5″ – 67-406 ETRTO-size. Compatible with most 20" unicycle, provided the wheel size is correct and you have enough clearance on your frame.