Advantage: Overcharge and overdischarge protection to increase the life of the battery. No memory effect, can be charged or discharged as needed without loss of capacity. Low self-discharge for maximum productivity and less downtime. Replacement Part: RYOBI: Ap4001, Tek4, Rp4900, Rp4410, Rp4400, Hp53lk, Ap4700, Rp4530, AP4302, RP4310, RP4470, RP4550 Compatible Models: RYOBI: HP53L 4V Lithium-Ion Reversible Screwdriver, RP4300 Motion Sensing Alarm with Remote, RP4205 TEK4 Inspection Scope, RP4530 Audio Plus Noise Suppression Headphones, RP4010 Professional Laser Distance Measure, RP4020 Professional Digital Multimeter, AP4001 4V Lithium-Ion Battery, RP4030 Professional Infrared Thermometer, RP4050 TEK4 Stud Sensor, RP4900 Portable Power Source.
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