Contract Window Security Bolt, sometimes called a Rack Bolt. The bolt is morticed inside the window and can be locked or unlocked via a separate splined key or with a fixed splined turn. The bolt has an internal sawtooth rack mechanism into which the splined key is inserted. The spline engages with the rack teeth and forms a gearing action which smoothly operates the bolt. Splined Key or Turn to be ordered separately. Comes with a 5 year mechanical guarantee and is suitable for use in all domestic, industrial and commercial environments. Available in an extensive range of finishes.