It boasts smooth and elegant movement to gently open the doors downwards. The opening angle adjustment can be carried out manually through the rotary knob, thus allowing to align nearby doors easily. The adjustment of the piston base plate within the "U" slot of the side bracket can change the door opening. KRABY grants a quick and easy installation, with no need to tension the strength. Directly installed on solid or wider aluminium frame doors and wide range of special adapters to suit small aluminium door profiles. All the parts (stay excluded) are in zinc alloy nickel plated and plastic..