SPNV 0512 Nitrogen Charging Bolts are used on some shocks considered to be "non-rebuildable". On these models the only thing keeping the shock from being rebuildable is the lack of a method for recharging it with high pressure nitrogen gas. If an SPNV 0512 is listed, this is one of those shocks.

The bolt is installed by drilling and tapping the shock body with an M5x0.8 thread in a location particular to the individual shock and so its installation is considered "Race Tech Only". If the body is drilled and tapped improperly the shock is useless and must be replaced.

Once the Nitrogen Bolt is installed the shock can be pressurized with a Nitrogen Needle (TSNN 01).