The Garrett ATX. It's hands down the most powerful pulse induction metal detector out there.  Features include:
GROUND TRACK (AUTOMATIC): Continuously measures ground mineralization and automatically adjusts itself for optimum performance.
MULTI-FREQUENCY (PULSE INDUCTION): To overcome the effects of mineralized soil and saltwater, it divides its power into multiple frequencies.
ELECTRONIC PINPOINTING: This Non-Motion All-Metal Mode is used to precisely locate a detected target's location in the ground, no need to switch modes to enhance detection.
VOLUME CONTROL: adjust to limit the response of large signals in order to better hear deep/faint signals.
SEARCHCOIL: enhances detection of small items without having to slow down the scanning speed of the coil.
FULLY COLLAPSIBLE: the ATX can be operated with its stem fully extended, fully collapsed, or anywhere in between.
Extremely versatile and can compact down to 20" for easy storage and transport. Packed with tons of features, the Garrett ATX is the top of the line machine.