Super Lube O Ring Silicone Lubricant Super Lube 18 Pinewood Derby Speed Tips title Need weights for your Pinewood Derby car? Tungsten weight has the heft you need. Much denser, so it's smaller for the same weight, allowing for more compact designs. The shop has Petroleum jelly on your O rings? It can break down rubber and cause leaks. Stick with Permatex O Ring Lubricant designed to protect, seal, and extend O ring life. , #oring #mechanic #mechanictips