The XP Deus II opens up serious underwater treasure hunting opportunities that most detectors can't match. With proper gear, you can hunt down to 20 meters (66 feet) - deeper than almost any beach or lake will require. Here's exactly what you need to transform your Deus II into a reliable underwater detecting machine.
Essential XP Deus II Underwater Equipment
XP Deus II Telescopic Dive Shaft
The standard shaft wasn't designed for underwater maneuvering. The XP Deus II Telescopic Dive Shaft gives you the compact size and durability you need when fighting currents or navigating tight spaces around pier pilings and boat hulls.
This shaft telescopes down for easy transport and extends when you need the reach. The build quality matches XP's reputation - we've seen these shafts handle years of saltwater abuse without issues.
Waterproof Coil Coverage
Your Deus II already includes a fully waterproof search coil, but double-check all connections before every dive. The coil can handle the full 20-meter depth rating, and the FMF (Fast Multi-Frequency) technology actually works better underwater than many single-frequency detectors.
Red Waterproof Plug - Critical for Deep Diving
This isn't optional gear - it's mandatory for any depth beyond 3 feet. The red waterproof plug replaces the standard gray plug and seals the control box for the full 20-meter depth rating.
The red plug doesn't equalize pressure like the gray one does on land, so you'll need to swap plugs when you're done diving. Failing to switch back can cause the keypad to swell or the speaker to stick.
XP BH-01 Bone Conduction Headphones
Regular underwater communication is impossible, but bone conduction changes everything. The XP BH-01 headphones transmit sound through your skull bones, so you'll hear target signals clearly even in noisy surf conditions.
These headphones work by sitting on your temples rather than covering your ears. You'll still hear ambient sounds for safety while getting crystal-clear detector audio. For scuba diving, they fit comfortably under most dive hoods.
Anderson Custom Dive Shaft Options
If you want alternatives to the standard XP shaft, Anderson makes excellent carbon fiber dive shafts in multiple colors. The carbon fiber construction is lighter than aluminum and won't corrode in saltwater. You can get them in black, yellow, green, or blue - useful for spotting your detector if you need to set it down underwater.
These Anderson shafts work with both the original Deus and Deus II, so they're a good investment if you're upgrading from the older model.
Saltwater Care and Maintenance
Saltwater will destroy any metal detector if you don't maintain it properly. The Deus II uses marine-grade stainless steel for all underwater components, but you still need to follow strict cleaning protocols.
Post-Hunt Cleaning Protocol
Rinse before disassembly: Always rinse everything with fresh water before unscrewing any plugs or connectors. Salt crystals will scratch O-rings and damage threads if you don't flush them out first.
Check plug tightness: Make sure the waterproof plug is snug before every dive. Hand-tight plus a quarter turn is enough - over-tightening can damage the O-ring.
Dry completely: If sand or water gets into any connectors, rinse thoroughly and let everything dry completely before reassembly. Trapped moisture will cause corrosion even in marine-grade components.
Heat Protection
Never leave the control box in direct sunlight, especially with the red waterproof plug installed. The sealed environment can't vent heat buildup, and you'll damage the internal speaker. This is particularly important when diving from boats where equipment sits in full sun between dives.
Depth Guidelines and Plug Selection
Gray Plug (Standard Use)
Depth limit: 1 meter (3.3 feet) maximum
The gray plug has a pressure-equalizing membrane that prevents the control box from swelling during temperature changes or altitude shifts. Use this for all land hunting and shallow water wading.
Red Plug (Deep Diving)
Depth limit: 20 meters (66 feet) maximum
The red plug creates a completely sealed environment for deep diving. It doesn't equalize pressure, so prolonged use on land will cause problems. Always switch back to the gray plug after diving sessions.
Beyond 20 Meters
Don't push the Deus II beyond its rated depth. At 70+ feet, you're getting into technical diving territory where equipment failure becomes dangerous. If you need to hunt deeper, consider towed detector arrays or ROV-mounted systems.
Underwater Detecting Techniques
The Deus II's multi-frequency technology gives you advantages underwater that single-frequency detectors can't match. Saltwater conductivity affects different frequencies differently, and the FMF system automatically compensates.
Start with the built-in diving program, but don't hesitate to adjust sensitivity based on conditions. Rough surf creates more electrical interference than calm water, so you might need to back off the sensitivity in choppy conditions.
The bone conduction headphones let you hunt by audio primarily, which is actually more effective underwater than trying to read the screen. Learn the different tones for various targets - it'll make you much faster at target identification.
Complete Deus II Underwater Setup Checklist
- XP Deus II with FMF coil (standard)
- Telescopic dive shaft or Anderson carbon fiber shaft
- Red waterproof plug for depths over 3 feet
- XP BH-01 bone conduction headphones
- Fresh water rinse bottle for post-hunt cleaning
- Backup gray plug for land use
- Microfiber towels for drying components
With this complete setup, you'll have one of the most capable underwater metal detectors available. The Deus II's depth rating and multi-frequency technology put it ahead of most competitors, and the bone conduction headphones solve the biggest challenge in underwater detecting - hearing your targets clearly.
