This is a Long PROGLO Starter w/Charger. This is used to heat Glow Plugs that require a long Glow Starter. This is a Blue Metal, spring loaded ProGlo Glow Plug. A threaded cap lets you remove and replace the battery. Threaded cap has a meter built into the cap. Has a convenient charger that will charge your typical 1200mAh Sub-C cell in about 12-14 hours. Sub-C battery is not included. INCLUDES: One Long PROGLO Starter with meter and One Charger SPECS:Shaft length: 2-3/4" Charger output: 120mA at 1.25V Charger Input Voltage: 110V AC (US Standard) REQUIRES: One Sub-C cell, SANP0250 The meter will only work when it is attached to the Glow Plug. Otherwise the meter will not show a volt reading from the battery.