The Detector - Explosive is a block from the Railcraft mod. This block is meant to output a Redstone signal based on the type of Minecart that passes in front of it. The Detector - Explosive will output a Redstone signal if any explosive Minecart is in front of it. Explosive Minecarts include the TNT Cart, the Wooden TNT Cart, the Pumpkin Cart, and the Gift Cart. They can be placed under or beside Minecart Tracks, and will output a signal to the side that has a small square. When a Redstone signal is active this square will turn red.