Brass Compression Fitting For Plastic, Copper, & Aluminum Tubing, 0.31 Inch Tube OD To 1/4-18 Male NPT, 90 deg Elbow

Plastic tubing is listed as a compatible material, though the product data doesn't break it down further by tubing type. What's worth knowing is that this fitting handles a 0.31-inch tube OD and connects to 1/4-18 Male NPT threads, so as long as your tubing matches that outside diameter, the compression sleeve should grip it the way it's supposed to. No flaring required, which makes it a good bit easier to work with on softer materials.