Max6mum security window restrictor lock has been specially designed to keep the window whether it be made from upvc wood aluminum or other metals from opening to far preventing your child or toddler from falling from or dropping large items from the window the max6mum security lock uses a 200mm twisted steel cable protected by a soft white plastic case that can resist a force of up to 100kg of force the window lock attaches directly to the window frame using the screws included with the pack