Requires Factory Installed End Clips Non-Tilt Window Type with Industry Standard 3/8" Tube Diameter Red Bushing Indicates Sash Load Weights of Up to 25 Pounds This heavy duty Tubular Spiral Window Balance for non-tilt type windows will replace 3/8 inch (9.5 millimeter) metal or plastic tube balances with a sash load capacity of up to 25 pounds (11.3 kilograms). The Series FR Balances require factory installed clips. There are four clips, as shown above. FS340, FS341, FS342 and FS343. Tube Diameter: 3/8 in (9.5 mm) Tube Length: 29 in (736.6 mm) Bushing Color: Red Minimum Order: 1 Package For Help on "Spiral Window Balances Removal and Installation Guidelines" click on this link. For Help on "How to Order Window Balances for Non-Tilt Type Windows" click on this link. How to Order Tubular Spiral Window Balances 1. To select the proper Tubular Spiral Balance, check diameter of the metal or plastic tube on the old balance: 9/16 inch is Series "FJ"; 3/8 inch is Series "FM" or "FR", depending on the fitting at the end of the rod. 2. Measure Tube Length only; do not include rod length. 3. Check color of Nylon Bushing. If White or Red, select a Standard Duty Balance; If Blue, select a Heavy Duty Balance. 4. Verify if fitting on rod protruding from the Nylon Bushing matches an illustration for Non-Tilt Type Balances. Select the appropriate series ("FM" or "FR") if balance diameter is 3/8 inch.