1. free maintenance
2. high discharge ability
3. low rate auto-discharge
4. long life cycle

1. maintenance free 2. low self-discharge 3. long life 4. uniform voltage can be kept among battery 5. no failure with in two year storage 6. quick starting touch-and-go 7. the battery can be freely used in three dimension directions 8. value-regulated, the pressure built-up inside of cells can be release during occasional discharge. 9. the battery can be fully recharged even after standing in a discharged stale of zero volt for one month. 10. safety: without acid leaked ,reliable opening and closing of safe-value prevent damage to equipment and explosion battery.