Whites Goldmaster Shooter DD (4x6) (50 kHz) Search Coil for Goldmaster V-Sat & Goldmaster III, Goldmaster 4B and GMT Metal Detectors. Elliptical 4x6 inch "DD" design provides superior performance in extreme ground, better sensitivity to physically smaller metal targets, performance in extreme trash and physically smaller foot print for working around obstacles. Longer but narrower detection window compared to similar sized search coils. Finds the good stuff in areas littered with trash.