Redline specific formed R7 tubing, bell shaped seat tube, press fit BB -86, and integrated seat post clamp. New Redline convertible dropouts allow the use of 15mm through axle or standard 3/8. The new Pro XL is designed to lead. R7 aluminum Redline specific formed tubing frame with convertible dropouts. Flight AL hollow forged cranks with 24mm chromo spindle. Redline Flight alloy sealed bearing cassette hub w/ 15mm through axle. 20” Sun Envy alloy rims w/ Tioga 20 x 1.85 Powerband(F) and 20 x 1.75(R) Powerblock tires.