The Welch Allyn 3.5 V Lithium Ion Rechargeable Handle has twice the on-time, half the weight, and fits more comfortably in your hand. Half the weight of traditional 3.5 V handles, fits all Welch Allyn 3.5 V Instrument Heads.  120 minutes of on-time (compared to 60 minutes for standard NiCad handles) Made of sturdy CYCOLOY engineering resin, Low-battery indicator 
Lithium ion battery technology that has no memory effect.
AC charging module is easily removable from the handle and has retractable AC prongs (model 71900 only). Optional charging well adapter allows the handle to be charged in consoles or 71110 Desk Charger