(1) 17 inch 20 lbs Gas Charged Lift Support. Reference numbers: LGP6-170-20, 613277, 613281, 613282, 613283, 613285. Red Hound Auto high quality gas props and lift supports have been designed to meet or exceed OE specifications. Easy do-it-yourself installation. Note: Replacing a single gas prop is not recommended for doors, hoods, etc. that have more than one prop. Replacing gas props or lift supports in pairs is always a good idea in order to keep the load balanced, maintain even resistance and avoid uneven wear. Undue stress on a single prop over the other results in diminished life for both props.