This Detech 15 x 12" SEF Butterfly Search Coil is for use with the Garrett Ace 200, 300, 400, 150, 250 and 350 metal detectors. By upgrading to this coil you will achieve the best depth and most accurate pinpointing. Compared to traditional DD coils, the patented SEF coil technology provides you with more stable operation, better ground balancing and the most accurate target identification. Search coil is waterproof and coil cover is included. Not compatible with Garrett Ace APEX models.