With a 90° rotation of the rear rod, rotating a serrated ring under the flange is achieved (the rotation is free). To lock the rod, a side button is pressed. Unlocking is only possible by inserting the key. The advantage is that the lock can be used without a key. It comes with 3 rods of 16/20/25 mm for different thicknesses. It is made of nickel-plated brass, including springs.