The Aquasol Battery Charger for Pro Ox-100 Oxygen Monitor is a must-have accessory for any welding professional who uses the PRO-OX 100 oxygen monitor. This charger keeps your monitor's 9V NiMH battery charged and ready to use, so you can always be sure that your welds are protected from oxygen contamination. Benefits: Keeps your PRO-OX 100 oxygen monitor powered up and ready to use Saves you money on batteries Extends the life of your PRO-OX 100 oxygen monitor Offers peace of mind knowing that your welds are safe Features Compact and portable design for easy use on the go Charges battery in just 4 hours Includes LED indicator light to show charging status Charger serves as a standalone power supply when operation will exceed one hour in length Can operate on 100VAC/60Hz, 120VAC/60Hz and 220VAC/50Hz configurations Compatible with different voltage and frequency specifications from around the world