Nokta INV40 15.5" x 14" Waterproof DD Search Coil for Invenio Metal Detector

The INV40 coil is compatible exclusively with the Nokta Invenio metal detector. This 15.5" x 14" DD coil is engineered specifically for the Invenio's electronics and mounting system, and it will not fit other Nokta models or detectors from other manufacturers. The mounting hardware included with the INV40 ensures a secure fit on the Invenio's lower shaft, providing the proper alignment and stability needed for effective detecting. The coil's DD configuration works seamlessly with the Invenio's detection capabilities to deliver excellent depth and target separation in various hunting conditions. If you own a different Nokta detector model, check our full range of metal detector search coils for compatible options.

The INV40 coil is fully waterproof and submersible, which means you can use it for surf detecting, shallow river hunting, and wet-sand beach searches without risk of water damage. The coil is rated fully submersible, making it suitable for detecting in streams, along shorelines, and in wet fields after rain. The waterproof construction also simplifies cleaning after muddy or saltwater hunts. Keep in mind that while the coil itself is waterproof, you must ensure your Invenio control box and other components meet the depth rating for your intended detecting environment. The included protective cover helps maintain the coil's condition during regular use in challenging wet environments.

The INV40 coil's 15.5" x 14" footprint provides wider ground coverage per sweep compared to smaller coils, which reduces the number of passes required to search a given area and increases efficiency during long detecting sessions. Larger coils detect deeper targets on larger objects such as relics, caches, and deep coins, making the INV40 particularly effective for open-field relic hunting and beach detecting where coverage speed and depth matter most. The Double-D configuration maintains target separation even at depth, so you're not sacrificing discrimination for size. This combination of wide coverage and DD design makes the INV40 ideal for efficiently searching large open areas while maintaining the ability to distinguish between targets in trashy conditions.

The INV40 coil purchase includes the 15.5" x 14" DD search coil itself, a protective coil cover to prevent abrasion damage from rocks and roots, and the mounting hardware required to attach the coil to your Nokta Invenio detector's lower shaft. The protective cover is especially valuable during relic hunts in rocky terrain or beach detecting where shells and coral can abrade the coil surface over time. All components are genuine Nokta parts designed for the Invenio system. The included mounting hardware ensures proper attachment and alignment on the Invenio's shaft, allowing you to start detecting immediately after installation.

The INV40 coil uses a Double-D (DD) configuration, which is specifically designed to handle mineralized soil better than concentric coils. The DD configuration handles mineralized soil well, providing superior ground balancing in iron-rich or saltwater-mineralized environments and maintaining stable operation while reducing false signals that can occur with other coil types. The DD design excels in areas with high mineral content, red clay, or black sand, making the INV40 a strong choice for challenging hunting conditions. Whether you're detecting on mineralized farm fields or saltwater beaches, the INV40's DD configuration delivers reliable performance. Learn more about how coil design affects performance in challenging ground at metal detector technologies.

The INV40 coil's weight is not specified in the manufacturer's documentation. As a 15.5" x 14" coil, the INV40 is larger than smaller coils, which does increase the overall weight of your detector setup compared to more compact options. The wider 15.5" x 14" search area allows you to cover more ground with each sweep, which can improve efficiency when searching large open areas like parks, fields, and beaches. The coil's size makes it particularly well-suited for relic hunting and coin shooting in open spaces where maximum ground coverage and depth are priorities. The included protective cover adds minimal weight while providing valuable protection against rocks and abrasive surfaces during regular use.

The INV40 coil is a genuine Nokta product designed specifically for the Invenio metal detector system. When you purchase the INV40 from Serious Detecting, you receive authentic Nokta parts backed by our customer support team. If you experience any issues with your coil, our team is available to assist you and help resolve any concerns. We stand behind the products we sell and work directly with manufacturers to support our customers. The INV40 includes a protective coil cover and mounting hardware, all manufactured to Nokta's quality standards. Explore the full Nokta Invenio detector lineup and accessories available through our authorized dealer support.