CSP86+, with 20cm diameter coil and 12oz weight, is a super compact professional water proof metal detector. It is so lighter than any metal detector in the market and weights similar to a cane. Such a light weight detector does not even need an armrest for long term carrying in hands. CSP86+ is connected to the smart-phone via an extension cable. The flexible but rigid metal/polymer structure makes it so portable and allows for shaping it into any desired form. CSP86+ is powered trough the headphone jack of the smart phone, no need for an external battery. It is an advanced ULF/VLF simultaneous multi-frequency metal detector with auto-ground balancing, discrimination and GPS. CSP86+ is calibrated and pre-programmed for best performance in saltwater.