With a standard 5 pin SD/GPX coil plug, the E1500 will run all GP/TDI mono coils, and recent coil testing has shown it will run DD coils in a fashion. While it is designed specifically for Mono, DD coils can be utilised and offer a peculiar and particular (imo) detecting option. The following links have a great rundown on the E1500 and it's coil requirements, with a general coil info link from Nenad Lonic.