1 PC Conversion Adapter Set. Red Adapter: 1/4” SAE (7/16”- 20 UNF) x 16 mm. Blue Adapter: 1/4” SAE (7/16”- 20 UNF) x 13 mm. · 【 Strong Seal】 With green strong rubber O ring seal to make no leakage, stay fit on your refrigerant charging port, great little tool kit.