[Size] 1/4 inch male air compressor quick plug to a female 3/4 inch garden hose inner thread and 1/4 inch male quick connecting plug and 3/4 inch male GHT thread. This is a standard size and can be applied in most cases. [Material] This RV winterize blowout adapter is made of heavy-duty copper which is durable, heat-resistant, sturdy, and corrosion-resistant. It is not easy to break or deform and can last for a long time. [Application] Winterize blowout adapter is used to winterize garden hoses, sprinkler systems, and faucets by blowing out water from water lines or plumbing to prevent damage from freezing in winter. It helps reduce the use of antifreeze. Convenient, safe, healthy, and environmentally friendly. [Easy to Use] Screw the water lines to the female or male threading side, then connect the quick plug to an air compressor line's female quick coupler. Turn on the air compressor and rotate the ball valve stem to open, close, or modulate the air flow velocity to blow out water from the water lines. Product Usage: RV garden water pipe connection. Material: Copper. Color: Yellow. Package Contents: 1 pair x RV Sprinkler Adapter. Only the above package content; other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture to be slightly different from the real thing. Measurement allowed error is +/- 1-3 cm.