One important consideration when choosing a portable handheld two way radio is power. Since batteries are usually the primary sources of power for handheld radios, the type of power cells needed is a key question. There are many makes and models of radios to choose from and there are a many different types and sizes of batteries available on the market, some of which are only compatible with specific radios, so the answer can be quite confusing.
In the case of Cobra FRS/GMRS two way radios, the battery options are specific, yet they vary significantly between different models within the product line, even between models that use the same type of battery. To simplify things, we've created a chart that compares all current Cobra consumer walkie talkies with the types, sizes and the number of batteries each radio requires.
| Model | Battery Type | Size | Quantity |
|---|---|---|---|
| CX112 | Alkaline | AAA | 3 |
| CX210 | Alkaline | AAA | 4 |
| CX312 | Alkaline/Rechargeable | AA | 3 |
| CXT135 | Alkaline/Rechargeable | AAA | 3 |
| CXT145 | Alkaline/Rechargeable | AAA | 3 |
| CXT235 | Alkaline/Rechargeable | AAA | 4 |
| CXT345 | Alkaline/Rechargeable | AA | 3 |
| CXT390 | Alkaline/Rechargeable | AA | 3 |
| CXT425 | Alkaline/Rechargeable | AAA | 4 |
| CXT545 | Alkaline/Rechargeable | AA | 3 |
| CXR725 | Lithium-Ion | CXR725 Battery Pack | 1 |
| CXR825 | Lithium-Ion | CXR825 Battery Pack | 1 |
| CXR925 | Lithium-Ion | CXR925 Battery Pack | 1 |
What I would suggest is to try asking in The Two Way Radio Forum. It's free, and you may find someone there who is familiar with the radio and can provide more insight or assistance with troubleshooting the issue.