Lift-Assist Torque-Adjustable Spring Hinge (HG-PA21-15) This external surface-mounted heavy-duty power lift-assist hinge (Product No. HG-PA21-15) is a torque-adjustable spring hinge that makes heavy top-opening lids easy to open and provides smooth, soft-closing action to keep them from slamming shut. This heavy-duty spring hinge offers a damper torque of 15 Nm (153 kgf-cm) over a maximum opening angle of 1 degrees. Like all products, our focus on product design delivers quality and durability. The construction of this lift-assist hinge features an SWO-grade steel spring and a 43 grade stainless steel hinge body, with a smooth plastic cover for a clean, neutral appearance. HG-PA21-15 Hinge Technical Details The design facilitates smooth closing action and easy opening even for heavy lids. For mounting on external surfaces. Torque-adjustable spring hinge allows the torque to be raised or lowered (+/-5%) by turning the torque adjustment screw. Torque peaks at either 2 degrees or 35 degrees, based on lid shape. Hinge body dimensions are 21 15 42 mm. Maximum damper torque is 15 Nm (153 kgf-cm), guaranteed to within 1%. We also have HG-PA21 hinges available in 2 Nm and 25 Nm of torque. Maximum lid opening angle is 1 degrees. The steel spring is SWO grade. The hinge body is stainless steel 43 grade. See Installation Manual.WARNING: This product can expose you to chromium, nickel, which are known to the State of California to cause cancer and birth defects or other reproductive harm. For more information, go to www.P65WARNINGs.ca.gov.