RADIOMASTERTX16S Battey 5000mAh 2S 7.4V XT30 JST-XH Plug TX16s Transmitter 1Pack

They definitely are proud of this battery. A 2s can certainly be found quite a lot cheaper.That said, I didn't feel like dealing with possible fitment issues. This battery does fit (obviously) in my MT12 radio and lasts quite a long while. I don't know exactly how long, because I haven't wanted to risk losing power mid-drive. I've charged it, went on a RC outing with my brothers the next day (8ish hours of crawling), shelved it for a few weeks, then went out again (another 8hrs or so) and it was still at 7.7v at the end of that day. This single battery can certainly last through a full weekend of RC activities, at least while in the Radiomaster MT12 4in1 that I'm using.Also, it's convenient being able to just plug the radio into my phone charger, rather than having to hook up yet ANOTHER battery to my charger.

I don't have any way to measure the capacity of this battery pack with a battery tester. But I recently bought this battery pack along with a RadioMaster transmitter. The battery seems to work fine.I'm thinking of testing the capacity of the battery pack by charging it to the maximum and then seeing how long the transmitter will run before the battery pack reaches 6.5 volts. I haven't done that yet because I haven't had that much time available that would allow me to check the battery often enough to keep it from over-discharging. If I find out more about this, I'll update this review with the results. At any rate, the battery pack seems to be working well.Update: The battery seems to be finally wearing out. It's got at least a couple hundred hours of use in a RadioMaster TX16S transmitter used for flight simulators (Phoenix, RealFlight And AeroFly). I'm getting about 3 1/2 hours use before the battery gets down to 6.8 volts. I used to get at least twice this amount of use before having to recharge the battery.I just ordered another new battery like this. You can ask yourself if 200-300 hours of use is good enough for this battery. I'm not really sure how long these batteries are supposed to last.

I carefully measured my Jumper T16's battery bay before ordering:W 42.5mm H 75mm and D 22mm.It barely fit dispite all of the measuring. The width was tightest but with a slight push on the battery it squeezed in. Instead of sliding the battery hatch in place, I now insert the top of the hatch mounting tab in place and then pull the cover down just enough to slide the bottom of the hatch back up to secure it. I had to modify the bottom of battery hatch a little but I got it in.This new battery is relatively heavy. The label says it's a 5000mah but in the description it mentions to NOT fast charge. No mention as to why but when I charged mine I set the charge to 2200mah. No issues with the charge, at least at the half the normal charging rate.****update****I've had this battery working in my Jumper T16 for a while now and I am very pleased with it's long lasting performance. I highly recommend this battery if you can fit it in your transmitter!

Came with a very good storage charge and took full charge easily and lasted a good amount of time on each charge.

Works well but overpriced, a DIY pack like this costs ~$2-4.

Initially bought this for a Radiomaster GX12 but then bought a Jumper T15 because of the screen. It fits the Jumper T15 perfectly and it was easy to install. Battery tray was removed and the 2S balance lead plugs right in.

perfect fit for the Radio master GX12

If your gear can use this 2 cell setup, do yourself a favor and get a few. Great quality!!!