Minelab Smart Coil 17″ and Carbon Fiber Shaft for CTX 3030 Metal DetectorThe waterproof 17 13 inch elliptical Double D coil provides maximum depth for specialized treasure hunting. It is also great for wide ground coverage in open spaces. The Minelab CTX 3030 Carbon Fiber Lower Shaft is a replacement or backup for the shaft that comes standard with the detector. When you use multiple coils it is great to have it pre mounted on a shaft for faster switching coils. Included Carbon Fiber Shaft Coil Cover Coil Hardware