TATTU14.8V 450mAh 75C 4S LiPo Battery Pack with XT30 Plug for Multirotor FPV 150 Size

looks perfect and had only flown twice. the third time my drone slowly started falling and beeping. thats when i checked the volts.

Does this work for a Traxxas slash 4x4 brushed?

i bought two of these 450mah batteries and one reads correctly as a 4s. the other one only reads 12.31 volts. somehow i lost a cell. the battery

Is this the correct mah for the eachine lizard95? been flying with 3s for over a year and think im ready for 4s. thanks for the help!