Pretec S65004 PCMCIA SRAM 4MB Card (Replaceable Battery)
Pretec SRAM cards feature high speed solid state memory technology with super low power consumption for maximum battery life.
Each SRAM card is designed with the dual battery system _ one replaceable but non-rechargeable 3V lithium battery (primary battery) and an on-board rechargeable but non-replaceable (secondary battery) for data retention. This design allows replacement of primary battery without data loss for approximately 20 minutes. In the event, digital signals on the card can be used to alarm the user whether the primary battery should be replaced to prevent the loss of stored data.