This bundle includes two G1/4" to 3/8" ID, OD 5/8" OD Compression Fittings and two Male to Female 90 degree Rotary Extender Fittings. Bitspower compression fitting for water-cooling systems. Compatible with tubing with 3/8" ID (inner diameter), 5/8" OD (Outer Diameter) and waterblocks with G1/4" threads. Thread Length: 5mm. Bitspower G1/4" Male to Female Extender with 90 degree Rotary Angle. Model: TR-77075-20885