A fitting incorporating a snap-fit sealing and locking device and methods of actuating the fitting and forming a seal between a length of corrugated tubing and the fitting are provided. The tubing can be corrugated stainless steel tubing having a jacket that at least partially covers the tubing. The sealing and locking device incorporates a bushing that is advanced through the application of axial pressure into a sleeve portion. Fingers on the bushing engage one or more corrugation grooves on the tubing and apply force to the tubing to collapse one or more corrugations to form a metal-to-metal seal. Distal motion of the bushing is inhibited after forming a metal-to-metal seal by contact between the bushing and the sleeve portion.