Tronian Tautron Magnetic Adapter Set

This is the same pair of magnetic adapters that come with the Tronian Tautron, sold on their own. You get two 510-threaded rings, sized for 0.5ml and 1.0ml cartridges, so you can keep one screwed into each of a couple of carts and swap between them with the magnet, or just replace an adapter that has gone missing. Your cartridge threads into the ring once, and the ring clicks onto the Tautron battery. They only fit the Tautron.