Per Purchase; 1 x RH + LH Restrictor, 2 x Fixing stud per restrictor 2 x Key per restrictorIdeal child lock this handy device restricts the opening of a window to 100mm and requires the use of a key to unlock.Suitable for uPVC, Aluminium & Timber windowsArm length: 105mm Screw centres: 37mm Frame part width: 16mmConforms to BS6375 Part 2:1987 Constructed from stainless steel & zinc alloy