Type: Ni-MH Voltage: 18V Capacity: 4000mAh Item Weight: 814g FCC, CE and RoHS certified, 100% compatible with the originals and may exceed the performance of OEM products No memory effect, can be charged or discharged as needed without loss of capacity Replace OEM P/N: PANASONIC EY9251, EY9251B Compatible Models: PANASONIC: EY3544, EY3544GQK, EY3551, EY3551GQ, EY3551GQW, EY3552, EY3552GQW, EY3796 (Flash Light), EY3796B (Flash Light), EY6450, EY6450GQKW, EY6950, EY6950GQKW Note: It's recommended that the battery should be fully charged and discharged 3 times after you receive the battery. For transport safety, our batteries are not fully charged before leave the factory. After use, please charge the battery after cooling. Package Includes: 1x Battery.