Features: This 0V LR20 D size battery adapter with 5.5x2.1mm female connector serves as a nonconductive battery eliminators, enabling safe power adapter connection for devices requiring D cell compatibility without actual voltages output. Crafted from durability steel, the terminals equipped spacer features a standardized 5.5x2.1mm female input (center positive polarity) for seamless integration with universally power supplies and electronics projects. Ideal for appliance technicians, electronics hobbyists, and smart home enthusiasts seeking reliability adapter based power solution for equipment like water heaters, gas detectors, or educational robotics set. Safely converts battery operated devices including emergencies lighting systems, industrial sensors, and children's educational toy into powered units through compatible 5.5mm adapters. Engineered for permanent installation scenarios, this nonrechargeable conductively bridge maintains stable current transmission between power sources and electronics while preventing accidental short circuit risks. Specifications: Component: Metal Length :Approx.58mm/2.28inch Diameter:Approx.32mm/1.26inch Cord Length:Approx.28cm /11.02inch Option Color: Red, Blue; Features:0V LR20 D size place holder tube disconnected fake battery with 5.5x2.1mm female input interfaces Package Includes: 1pc Battery Adapter note: Please allow 1-10mm errors due to manual measurement. Due to the differences between different monitors, the picture may not reflect the actual item color.