The park tool sg 72 oversized adjustable saw guide accurately guides a hacksaw to cut aero shaped seat masts and seat posts up to 275 70mm as well as fork steerer tubes and other round tubes from 1 116 to 1 34 27mm to 45mm the sg 72 features two different cutting slots mdash standard and carbon cutting blade widths mdash in a hardened steel body with molded contact points to protect tubes and frames park tool sg 72 oversized adjustable saw guide the sg 72 cutting