This type of gas rig is a truck with a large spool of coiled pipe. This spool is capable of uncoiling the pipe (coiled tubing) and lowering it into a well bore to drill, clean out, circulate out obstructions, or “jet” the well with compressed gas in order to initiate gas production. The coiled tubing is usually 1” to 2 ½” in diameter. The coiled tubing passes through an “injector head” which straightens the tubing by bending it in order to lower it into a well. Coiled tubing is a relatively unique item and requires significant engineering and operational skill to properly use. It is limited to working in wells 18,000’ and shallower. The CTU (coiled tubing unit) can be mounted on a skidded structure for easy transport to offshore wells. Schumberger, Cudd Pressure Control, and Halliburton a few of the companies that provide this service.