Review on Enviro Safe 3226 Can Tap Gauge by Bob Fasho

As others have said, the needle valve is not long enough to pierce the seal in the 12oz blue can of coolant sold at Revain. And when you get to the point where you understand this, you will find yourself in a dilemma - ESPECIALLY IF the glass is punctured just a little so that it leaks a little. Apparently there are adapters to make it work, but other users also have complaints about it. The green rubber pad in the T-handle fitting is too thick for the needle to pierce the glass. So take that spacer off and either cut it thinner like someone suggested or take it to the hardware store and find the right size, thinner. If you try to make your own upholstery, you run the risk of failing. The "Enviro-Safe" manufacturer (wrong!) should at least be AT LEAST proactive and explain all this up front so their customers don't have a bad experience and unintentionally release refrigerant 134a into the atmosphere.