Review on Convenient Self-Sealing R134A Can Tap Valve Refrigerant Dispenser: Versatile Brass Valve Tool with Tank Adapter for AC Freon Charging Hose (Blue) by Mark Allen

Watch eUQYjodqEPo and DJp5g7h5EBs videos on YouTube or search "self-sealing jar" to understand when and why you need it. This applies to the R-134a closure can. The ascent is NOT controlled by the valve handle, but is fixed. It presses on the Schrader valve on the cylinder (so if you tighten it, there will be a refrigerant leak). The valve must then open and close to release the refrigerant. Problems: 1. "Open arrows" point in the wrong direction. 2. Valve WILL NOT LOAD when open. The fact that the open arrows are pointing in the wrong direction tells me there is no quality control. No wonder the valve doesn't work. Give that junk back.