The Blue-Point Universal Fuel Tank Filler Neck Adapter pops on the filler neck of virtually any vehicle for easy EVAP leak testing. The one-size-fits-all adapter creates an airtight seal, and can be reused again and again. Use the adapter for smoke testing or vacuum/pressure-decay testing the EVAP system. The Blue-Point Adapter is made of a special substrate that won't break down or crack, and is backed by a five-year warranty. To use, simply remove the gas cap, pop the adapter on and connect a smoke machine or any leak detection device to the adapter.