Accurately guides a hacksaw to cut aero-shaped seat masts and seat posts up to 2.75" (70mm), as well as fork steerer tubes and other round tubes from 22mm to 45mm (7/8" to 1-3/4"). The SG-7.2 features two different cutting slots — standard and carbon cutting blade widths — in a hardened steel body with molded contact points to protect tubes and frames.7

More info: https://www.parktool.com/assets/doc/product/SG-7.2_instructions.pdf