Welcome to our shop! Dimensions: 53.4 x 53.4 mm for general buckle seat; 5 grades of stainless steel reinforcement arms: 125mm long, 7 grades of stainless steel reinforcement arms: 166mm long. Plastic steel model: only suitable for inward opening windows with 43mm hole distance handles, the support arms are screwed in and the seat of the buckle is directly placed on the handle for use. The distance between the edge of the handle and the window sash should be less than 16mm, otherwise the buckle should be reversed. Universal type: it can be used for aluminum alloy/plastic steel windows that open inward/outward. The support arm and the buckle seat are directly drilled and screwed. Material: thickened stainless steel, two specifications are optional: 5-speed/7-speed; 304 stainless steel springs to solve the situation of loose rivets and prevent the window sash from shaking when the wind blows. Correct installation method: misplaced installation, avoiding contact between window arm bracket and the buckle seat when closing the window, which will cause the window to fail to close. Package Quantity: 2 pieces (with accessories) Product color: Silver Product dimensions: 53.4 x 53.4mm; 125mm, 166mm Note: Manual measurement, please allow 1 - 3cm error!!! 100% Satisfaction - Our customers are our priority. If you find any problems with the products after receiving the goods, such as damage and incorrect quantity, please contact us immediately. We do our best to provide you with satisfactory after-sales service.