This is a NX Purge Valve Kit complete with the -4 AN inline adapter and a pushbutton activation switch.   Comes with a 3 foot length of 1/8 inch purge discharge line made with nylon air brake hose.   Bleeds vapor from nitrous lines to eliminate any hesitation or stumble upon activation.   

Also available with a -6 AN line adapter (9/16 inch thread fittings instead of 7/16 on -4 AN)------if you do not specifically request the -6 AN, I will ship the -4 AN.