AVX Corporation has developed a low-profile, board-to-board connector designed specifically for miniature and handheld portable equipment applications. Designated the 5805 series, the connector has a 0.4 mm pitch and a 1.0 mm stacking height. A double-sided contact structure adopted for mating lock enhances the components resistance to vibration and drop shock. The 5805 series employs a twin-rib-shaped plug side contact that eliminates foreign obstacles, such as splash flux, from interfering with the contacts, improving the contact reliability. A fine lock mechanism with firm clicking response ensures a secure termination and also increases the retention force when connectors are unmated. The board-to-board connector allows users to easily check conductivity and short-circuits in the connector under mated condition by offering a test connector that is able to withstand a large number of mating cycles. Because no metal is exposed on the bottom of the connector, the 5805 series is suitable for high-density package.