compression gas springs type, also known as free type gas spring, supporting bar, nitrogen spring is a high-pressure gas sealed in the cylinder, the piston produced by the elastic features of the product. The product does not need to work at the outside power, constant lifting force. Fully open the rear door is widely used in automobile, hood, back door luggage, mechanical equipment, construction machinery, furniture, fitness equipment, and other fields. It has a long life, easy to control, no maintenance and so on. High quality and long service life. Easy to install. Suitable for For 2006-2010 Hummer H3 Instructions: 1. Use Safety stands whenever a procedure requires you under the vehicle or supports. Or have someone hold the lid open for you so that they can raise or lower it as needed. 2. Before removing the old lift support, inspect the end connections and compare them to the units on your vehicle to make sure that they are the same As well as the extended length. 3. Remove the old support from the vehicle by placing a small flat headed screw driver under the U shaped band on the ends of the support. Slowly turn the screw driver and it will lift up on the band approx.1/8 inch, then pull the support away from the vehicle and it will release. 4. To install the new supports do the same procedure in reverse. DO NOT jam the new support end over the ball socket without lifting the U band slightly or damage may occur. 5. Lift Supports need to be installed fully extended. In most cases you just can't compress them unless they are on the vehicle. 6. If the ends are not lining up the support may need to be turned. To do this attach the shaft end of the support to the vehicle and then turn the entire body of the support clockwise unit the ends line up. Colour:black Material:metal Size: Compressed Length: 15.8cm Extended Length: 40cm Package Contents: 2 x front hood gas li