These are the GT2 Tires for the Savage X by HPI. FEATURES: Rubber construction, S compound On/off road tire tread HPI-racing on profile of tire INCLUDES: Two tires Two inserts REQUIRES: Wheels (HPIC4007) SPECS: Outer Diameter: 160mm (6.3") Inner Diameter: 78mm (3.07") Width: 86mm (3.4") mcw 3/31/06 ir/jxs