Minelab and Detech 21*17 SEF coil

Detech 21x17" SEF Butterfly DD Search Coil

The Detech 21x17" SEF (Symmetrical Electromagnetic Field) Butterfly DD Search Coil is designed for maximum depth and superior performance in all terrains. This large elliptical coil provides exceptional ground coverage while maintaining excellent stability and accurate target detection.

Built with patented SEF (Butterfly) technology, this coil delivers enhanced sensitivity and improved depth compared to standard DD coils, making it ideal for serious detectorists searching for deep targets.

Key Specifications:

• Coil Type: DD (Double D)
• Technology: SEF (Symmetrical Electromagnetic Field) – Butterfly
• Size: 21 x 17 inches (elliptical)
• Weight: approx. 907 g
• Waterproof construction
• UV protected housing
• Coil cover included

Compatibility:

This Detech search coil is compatible with:

• Minelab Explorer series
• Minelab E-Trac
• Minelab Safari
• Minelab Quattro
• Minelab Sovereign XS / XS-2 / XS-2A / XS Elite / GT
• Detech Relic Striker

Features:

• Patented SEF technology for improved performance
• Designed for increased depth and ground coverage
• Stable operation in mineralized soils
• High sensitivity to deep targets
• Reinforced ribbed housing for shock absorption
• Manufactured using high-quality polymer with glass fiber reinforcement
• Advanced electromagnetic shielding for minimal signal loss
• Waterproof and UV resistant
• Reliable performance across a wide temperature range

Performance Benefits:

• Up to 10–15% increased depth (depending on ground conditions)
• Improved ground balance
• More stable operation in difficult terrains
• Enhanced sensitivity and target response
• More accurate target identification
• Excellent pinpointing despite large size
• Better overall field performance

Intended Use:

• Deep coin hunting
• Relic and artifact hunting
• Large area coverage
• Open field detecting
• Use in mineralized and challenging terrains

Warranty:

• 2-year manufacturer warranty

Why Choose This Coil?

The Detech 21x17" SEF Butterfly coil is built for maximum depth and efficiency. It is the perfect upgrade for detectorists who want to cover large areas quickly while still achieving deep and accurate target detection. Ideal for open terrains where depth and coverage are critical.