The 16340 batteries are a bargain. The cost is about the same as the CR123 batteries, however the added benefit is that the Ready Up Gear 16340 batteries make the Spark Light brighter and can be recharged up to 800 times. They are now a part of my EDC.

Another really nice product from the Ready Up Gear is the USB Rechargeable 16340 batteries which will replace the traditional and expensive CR123A batteries. Upon receiving the batteries you will need to fully charge them. If using the USB port the battery indicator light will be red changing to green when fully charged. They can also be charged on a traditional battery charger. The batteries have an overcharge, discharge, overheating and short circuit built in also. The batteries also put out 3.7 V which makes your light as efficient as it can be.
With a capacity of 650mAH these batteries will last a very long time, of course that depends on the item the battery is being used in. They will run 800-1000 charge cycles if properly maintained.
I am using them in a Triad ASP light and I have noticed a big difference in light output using the Ready Up Gear rechargeable batteries compared to a new CR123 battery. Overall these batteries perform like they are supposed to.

I use these in multiple electronics and they work great. For the price uou save money after the first couple of rechargex.

Just as advertised…..Significantly more light than regular batteries. Well worth the price.