Injector hose comes complete with a R1234YF coupler. To inject the oil or dye, simply connect the injector to the low side of the A/C system and twist the handle until you reach the desired amount.
Mastercool 134a Oil and UV dye injector. Add refrigerant oil or large amounts of UV leak detection dye. Includes a low side coupler. 1/2" ACME-M x 1/2" ACME-F (R134a). Instruction pdf.
Can also be used for fluorescent dyes. Just fill the barrel with the amount of oil needed (measurements are marked on the barrel body) Connect the injector fitting to the low side access port on the...