Here’s a tip we’ve learned from experience. To fill the struts with nitrogen, a fill kit is necessary. High-pressure braided lines are also a must when working with up to 3,000 psi of nitrogen. The fill kits seemed expensive, and we thought for sure we could piece one together to save some coin. Our biggest mistake was trying to avoid the $45 special no-loss nitrogen chuck that is included in this pictured ORI fill kit. That mistake resulted in a bent Schrader valve on one of the struts and two broken standard push type air chucks as well. It was also tough to fill the strut with any level of control. When everything was said and done, after we bought the special nitrogen chuck, we were within $25 of just buying an ORI fill kit. We had also spent time and fuel running all over town trying to piece one together, not to mention having to replace one Schrader valve. Our advice: Just buy the fill kit from ORI and don’t try to pinch pennies.