Flashlights
Streamlight ProTac 1L-1AA battery
1 × 3V lithium cell
Short answer: one CR123A lithium or one AA alkaline/lithium primary — not both at once. Remove the tail cap; Streamlight’s battery positioner accepts either cell with the positive end in first. Higher output on CR123A. Operating instructions say the light is not designed for a rechargeable CR123 / RCR123A.
Other batteries in this device
How to replace it
| Compartment | Tail cap |
|---|---|
| How to open | Remove the tail cap. Insert one CR123A or one AA cell into the tube (positioner accepts either). Positive end of the cell in first; replace the tail cap. |
| Orientation | Positive (+) end toward the head (per Streamlight operating instructions) |
| Access | Tool-free |
| Notes | Use only one cell at a time. Output and runtime differ by chemistry — see OEM data sheet. |
Important
- Do not use a rechargeable CR123 / RCR123A — Streamlight instructions explicitly disallow.
- Do not mix or stack CR123A and AA together.
- Streamlight lithium battery notice: prefer Streamlight / Panasonic / Sanyo / Energizer CR123A or Duracell 123 for non-rechargeable lithium products.
- Strobe mode warning for photosensitive epilepsy (OEM instructions).
Sources
Helpful for this device
Optional tools for opening, testing or charging — separate from the battery answer.
- Battery storage organiser (AA/AAA/coin)
Keep spares sorted; reduce coin-cell short risk
- Fluke 101 Digital Multimeter
Accurate open-circuit voltage and basic electrical checks
New battery but still not working?
A fresh 1 × CR123A should restore Streamlight ProTac 1L-1AA if the battery was the problem. Work through the checks below before replacing the device.
- Check orientation
Confirm the cell is seated correctly: Positive (+) end toward the head (per Streamlight operating instructions)
- Check the battery type
This device needs 1 × CR123A (lithium). Same size does not always mean the same battery.
3 more checks
- Check known model-specific issues
Do not use a rechargeable CR123 / RCR123A — Streamlight instructions explicitly disallow. Do not mix or stack CR123A and AA together. Streamlight lithium battery notice: prefer Streamlight / Panasonic / Sanyo / Energizer CR123A or Duracell 123 for non-rechargeable lithium products.
- Confirm the battery itself
For most coin cells, fitting a known-good fresh cell of the correct code is simpler than capacity testing.
- Still not responding?
If a correct, fresh battery installed properly does not restore the device, the fault may be elsewhere — the device may need service or replacement.