Waldo;
The fittings are compression but a double ring style. Once the pipe is seated in the fitting, a rear and a front ring seal the pipe in. I used 3/8" and 5/16" lines on my engine. I bought a bender from Summit Racing and it broke in half after about five bends on the SST. Then I bought an Imperial Eastman bender from an aircraft parts supplier in Georgia. What a difference! Made all my bends without a problem. Was well worth the small additional price. Think it was a model 470 or something like that. Bends 1/4, 5/16 and 3/8" tubing. Get a Sharpie felt pen and mark your bends for each radius length and also make sure you make a small line in the side of the pipe where you want the bend to go. When you position it in the bender, it makes life a whole lot easier. Good luck!
