SledgeHammer’s Hinged Bolted Stop collars are combine in two pieces and hinged at one end. On other end, a single Bolt is used to tighten the Collar to the casing. This design does not make any marks on the casing. On locking it can be tightened for a holding force upto 10 times more of the Centralizers Starting Force as per API 10D. These Stop Collars undergo a special Iron Phosphate coating process to prevent from Rust then coated with special Polyester Powder they are available in all sizes ranging from 4 ½ “ to 20 ”.