EBL C Size Battery Adapters, AA to C Size Battery Spacer Converter Case Use with Rechargeable AA Cells - 4 Pack

Well built product works fantastic and no more searching for that size at little stores.

I have two devices that use C batteries, and neither of them use much power. I didn't want to have to buy C batteries just for these two devices, so these adapters work great. You can just keep them in the device and swap out the AA batteries when it needs to be changed.

These sleeves work great for using AA batteries in place of using C batteries

These are pretty basic, a plastic sleeve that slips over an AA size battery so they fit in place of a C battery. They work flawlessly in this regard, with the AA battery fitting inside snugly. The plastic feels strong, not like it will crush or fall apart easily, so I expect they should last a long time. They're working well for allowing me to use AA NiMH batteries in an old radio that takes C batteries, resulting in my not having to have specific batteries and a charger just for that radio. Well worth the price for that convenience.

About battery cell adapters..... Adapters such as these are simply a sleeve to center an AA cell in a compartment sized for a larger C cell. In order to work, the contacts on the device must be able to meet with the smaller diameter ends of an AA cell. Several other reviewers mention this. With an AA cell in hand, you can generally "eyeball" whether this will work by inspection before purchasing. For spring loaded devices, pushing in the adapter with its AA cell will sometimes result in the AA cell pushing through the sleeve. With multiple cells end to end, this can be a frustrating task. This can sometimes be corrected by wrapping some tape around the AA cell to increase the friction. If you can get this system to work, there are other considerations. An AA cell usually can't provide the amperage of a C cell so, some devices may deliver neither the brightness nor volume, etc. expected. Other devices may not work properly at all. Also, an AA cell can't provide the amp-hours that a C cell does thus, operating times may be shorter. I use these adapters with non-rechargeable Lithium AA cells (or, AAA cells, see below) in my seldom used equipment such as an emergency radio or lighted precision reticle since the Lithium cells are less prone to leakage, over time, than alkali batteries are, and, to my knowledge, are not available in C size yet. It seems the non-rechargeables are only available in AA, AAA, and 9v. That's where these are a good workaround. Another alternative is this adapter which I have also used. https://www.amazon.com/dp/B0851DLJ3T?ref=ppx_yo2ov_dt_b_fed_asin_title Here a combination of multiple AAA cells can be used (in parallel) to replace a C cell in many cases equaling, or exceeding, the C cell's original capacity. While contact alignment is not generally the issue, size may be. If the device using C cell compartment is tight from a diameter perspective, sometimes these adapters, with a full capacity of 4 AAA cells, will not fit or, will get jammed and difficult to remove. These adapters also introduce a third metal to the circuit. There is now the additional risk that different metals in contact with each other (essentially forming a "battery" in their own right) will begin an electrochemical reaction resulting in oxidative corrosion. Again, your mileage will vary. Both of these adapters have their function and purpose. They may well work for you. Hope this helps.