XtremepowerUS 1/4" Deluxe Adjustable AC R134a Quick Coupler HVAC Connector Adapter H/L Freon quick couplers adapters Side fitting for A/C manifold gauge set (R-134A) type Blue: Low side quick connector/adapter (1/4" SAE male flare) Red: High side quick connector/adapter (1/4" SAE male flare) Quick, easy connect/disconnect, high flow