NPT DP DP Deckplate Add O for CP and Pro Kits. The Improved LeakTronics Deck Plate ™ with advanced noise filtering technology makes listening through concrete, brick, rock or any other solid surface simple. With a more rugged, slimline design, either combining the deck plate with our pressure rig or just listening under normal pressure, pinpointing a leak through solid surfaces is simple. When combined with our pressure rig, the DeckPlate can listen deeper through concrete and compacted soil.