One unit doesn't have a trigger cover or battery holder and cover. The nVent ERICO Cadweld Plus Impulse Exothermic Welding Control Unit is a welding equipment unit designed for control and ignition of exothermic welding reactions. Manufactured by ERICO in China, this Elec Ignitor unit provides precise control and efficient welding capabilities for various welding applications in the manufacturing industry. With its advanced technology and reliable brand reputation, it is a valuable addition to welding processes for achieving high-quality welds and consistent results.