Superior Tool 5239 Internal Pipe Wrench Kit Eliminates damage to threads, walls, & external nickel or chrome finish Exclusive "Cam Action" provides nonslip grip on the inside of nipples, pipes & fittings Heat treated alloy steel Eliminates the possibility of damage to threads, walls and external nickel or chrome finish Exclusive &#039;Cam Action&#039; provides non-slipping grip on the inside of nipples, pipes and fittings and can be turned either way Heat treated alloy steel Included are sizes: 3/8&#034;, 1/2&#034;, 3/4&#034; and 1&#034;