Nokta INV28 11x7 DD Waterproof Coil for Invenio Metal Detector

The Nokta INV28 is an 11-inch by 7-inch elliptical DD search coil built for the Nokta Invenio metal detector, delivering wider ground coverage and sharper target separation in mineralized soil and trashy sites. Invenio owners working parks, beaches, and relic fields where multiple targets cluster within a sweep reach for this coil when the stock configuration misses masked finds. The Double-D geometry excels in moderate-to-heavy trash and wet saltwater sand where concentric coils struggle with ground noise.

What's Included with the Nokta INV28 Coil

• Nokta INV28 11x7 DD waterproof search coil for Invenio detector
• Protective coil cover
• Mounting hardware

Why Invenio Owners Reach for the INV28 Coil

• Wider 11x7 elliptical footprint covers more ground per sweep than smaller coils.
• Double-D configuration separates adjacent targets in trashy park sites where iron and foil mask good finds.
• Fully waterproof construction handles wet sand, shallow water, and rain without performance drop, extending your hunting window to surf lines and freshwater wading zones.
• Direct-fit mounting for Invenio detectors requires no adapters or balance adjustments, swap takes under two minutes in the field.
• Included coil cover protects the housing from rocks, roots, and abrasive surfaces, extending the coil's lifespan significantly.

Sharper Target Separation in Trashy Park Sites

Urban Park Hunts with Heavy Iron Contamination

The INV28's DD field pattern rejects ground minerals and isolates individual targets in iron-heavy turf where pull-tabs and bottle caps cluster around benches and playground edges. The 11x7 ellipse fits between playground posts and under low-hanging equipment, maintaining the coverage advantage without sacrificing maneuverability. Run the Invenio's discrimination at mid-range and let the coil's geometry do the separation work.

Wet-Sand Stability on Saltwater Beaches

Saltwater mineralization causes concentric coils to chatter and false in the surf zone; the INV28's DD geometry cancels that ground noise and holds stable tone response across wet-to-dry transitions. The waterproof housing handles wave splash and submersion to the shaft collar.

Specifications

• Compatibility: Nokta Invenio metal detectors
• Coil Size: 11in x 7in (28cm x 18cm) elliptical
• Configuration: Double-D (DD)
• Waterproof Rating: Fully waterproof (coil and cable)
• Included Accessories: Coil cover, mounting hardware

Why Buy from Serious Detecting

Serious Detecting is an authorized Nokta dealer, every INV28 coil ships with the full manufacturer warranty and our 30-day return policy. Our team runs Nokta metal detectors in the field and can answer setup questions specific to the Invenio platform. Free shipping applies to all coil orders. We price-match any authorized dealer and stock a full range of metal detector search coils: DD, concentric, monoloop & SEF upgrades for cross-platform comparison when you're ready to expand your coil arsenal.