Yale Doormaster Universal lock uses the latest patented technology from Yale to ensure security and simplicity of installation. It is designed to replace 100% of PVCu door locks with a 35mm or 45mm backset and a 16mm faceplate. The revolutionary new range means that if a multi-point lock is broken, the lock - rather than the whole door - can be replaced. The one-piece mushroom rollers ensure smooth operation and help prevent separation. These easily adjustable rollers create a weather-tight seal to protect the interior of homes against the elements and help to keep warmth in. The centre hook protects against attack, and helps in preventing separation. Doormaster is supplied with a fully assembled one-piece keep, which includes the patented Uni-packer system for fast, easy and reliable installation. Fixing tabs make fitting easy and more secure. Doormaster locks are suitable for most PVCu, Composite or Timber doors. They are available for doors with a single hook or bolt in the centre of the door, and also for locks with additional hooks or bolts at the top and bottom of the door. 10 year guarantee. The YALYDMUNI45 Doormaster Universal Replacement PVCu Lock is suitable for the following dimensions Backset 45mm. Faceplate 16mm.