Brass Compression Nut For Plastic, Copper, & Aluminum Tubing, 0.31 Inch Tube OD

Pressure capacity on compression fittings like this one depends on tube size, so the 2000 psi maximum doesn't apply equally across the board. That figure comes with a 4:1 safety factor built in, but smaller or larger tube sizes will shift where that ceiling lands. For 5/16 inch OD tubing specifically, check the rated pressure for that size against your system requirements before installing.