(Pack of 6) C Battery Adapter, AA to C Battery Adapter Converter Spacer, C Size Battery Adapter

Worked as well as more expensive products.

These fit AA batteries perfectly. Rechargeable batteries are a tighter fit but if you're patient you'll be successful. I use these in an old school boom box and and it powered the CD player for 6 hours at half volume.

These seem like decent product for the money

These adapters work great to convert an "AA" battery to “C” size, and the Product description is accurate except for one thing I will talk about later. Most important to note is the size of the "AA" battery you will use. They say, "it doesn't fit some rechargeable batteries", and they are correct. There are 3 grips that hold the "AA" bat, and 6 adapters measure between 0.542" - 0.552". I used a standard alkaline battery which measured 0.538" dia. and it fit perfect with all 6 adapters. I also tried an extended capacity rechargeable that measured 0.568" dia. and it does not fit 2 of the 6 adapters, but does fit very tight in the other 4. Another consideration is the weight of an AA battery in the adapter. I measured a standard alkaline "AA" battery with the adapter at 0.74oz/21g. The standard "C" size alkaline battery that I have measured 2.5 oz/70.9g. I gave 5 stars because they work well, are built solid, and they do point out the size and weight limitations.One error I found in the description is, “Weight of c cell battery adapter: 0.25oz/7g”. It should say 2.5oz/70g which more closely matches my measurements.

Brilliant idea whoever thought of this. I use these for everything thing that takes C batteries.

All you have to do is add a AA battery inside this and it acts as a C battery. I have many of them, In case of emergency like a hurricane they will help enable powering of the radio.

I assumed that since these adapters exist, AA's and C's were the same length, they are NOT. AA's are 50mm long and C's are 46mm long. These work fine IF you have room for the extra length (a long spring). I bought these adapters for use in a vintage toy that uses four C batteries in two rows of two batteries with a plastic compartment the exact length of the batteries and no springs, just tabs. They would not fit; the two AA's end-to-end were 8mm (~5/16") longer than the available space in the battery compartment.

Worked great