- Capacity : 4000mAh.
- Maximum Discharge Rating: 40A.
- Size: 21700.
| Manufacturer | Fogstar |
| Model | FS4000 |
| Capacity | 4000mAh (4.0Ah) |
| Maximum Continuous Discharge | 40A |
| Nominal Voltage | 3.6V |
| Fully Charged Voltage | 4.2V |
| Size | 21700 |
| Terminal | Flat-Top |
| Protection | Unprotected |
Always use a case for safe storage when not in use. Never in your pocket, purse etc. Keep away from keys, coins and small metallic objects.
Batteries should never be charged in a mod. It's good practice to charge batteries on an external charger that is correctly rated for Li-Ion cells. Never leave them charging unattended and they should be removed when fully charged.
Batteries should be periodically inspected for tears and rips. Never use a batteries with a damaged PVC wrap, either recycle the cell or repair immediately.
Do not over-stress these batteries. Batteries should be suitable for the application (correct size, amp draw etc).