Matrix High Output Large Type Airsoft NiMH Battery (Configuration: 8.4V / 4000mAh / Large Tamiya)

"bought the 12V 4500MAH. THIS THING IS MASSIVE!!! it unfortunately does not fit in the a1 style stocks found on m16s because of the long screw that goes all the way down the stock to screw into the spring guide. regardless of the long screw it still sits high in the stock so it peeks up a bit but if you file out a the notches that fit parallel in the upper receiver, you should be able to fit it in there, again the long screw will prevent you from fitting this battery in the stock. other than the fitment issue, this thing performs amazing. much higher ROF than a standard 9.6v. i will be buying the 12v butterfly type battery to see if that fits in A1 stock.

"Awesome battery if you have the room for it. This thing seems to last forever and the deans connection is done well. I have one that is 2 years old and still works and for that reason I bought 2 more recently for a couple of my AEGs.

"Everything works good about it and the battery lasts weeks. Just make sure it fits in your gun and you're good.

"Had this for 8 months and love it. Charge lasts forever and really woke my gun up without misfeeding issues. I got it to fit in my m16 stock after cutting a notch out of the stock but it's better than having it outside and I never have to switch it out or recharge during a game.

"This battery barely fits my G&G Combat Machine AK-47, but after filing the ends of the screws and a bit of wresting with it, it fits and runs like a charm. I have ad absolutely no problem with the gun or battery, it lasts for HOURS! Great buy

"This is an excellent battery. Large and lots of energy. My favorite part about this battery is that it fits in the stock of the Matrix M240b. Lets me shoot all of the bbs out of my box mag without having to worry. I get to do defense games knowing that I'll run out of bbs before I run out of power with this battery.

5/5 Stars
Recommended for people who are trigger happy.

http://www.evike.com/products/50809/

"Awesome battery... seems to last forever(3 hours of heavy auto firing) and ROF increased dramatically.
I guess the only downfall would be its size.
It's 1.5" w X 1" h X ~8.5" L.
I currently have is inside the stock( Model: Stock-MTX-MK2-WW) of my M249 MKII but it took a bit of doing and it fits like it was made for the stock...snug but not too snug, ...and adds to the overall weight of the already heavy LMG.

You will need to remove the stocks butt plate(the slide cap and metal part) to get the battery in, making sure you have the LMG wires on the down side of the stock when inserting. Push in slowly and firmly so you don't pinch the LMG wires.
Once in put the metal butt plate back on...it will be snug.
There is enough room for all the extra wire and fuse to be tucked in nicely.
I don't even bother removing the battery to recharge it seeing as it easily last all day of heavy usage.
When I do charge it I set the smart charger to the 2 amp setting as its a big battery.
I may buy another for my other M249(yes, I have 2) which has a 10.8v battery (Model: BAT017) in the stock. This battery needs to be installed from the front end of the stock as one cell is sideways... this battery also fits snug.

So if you have an M249 (CA or A&K), these 2 batteries(12v/10.8v) will fit in the stock.
I don't know if they will fit in G&P(or others) M249.

"This thing is OVERKILL... I put in my KWA M4 (external battery holder) and i swear it shot like 30 RPM's! If you have the money for OVERKILL, please get this. OR if you have a M249/Para... OVERKILL X2!!!!! lol

"literally have had this battery so long i've forgot. at least 5 years for sure. its just now showing signs of not lasting as long as it used to. im going to buy it again. its main use is in my M60 witch fits great in the box mag, BUT you may not believe me but i DO fit this battery in my G&G Rk-47 Blowback. back in its hay day my battery would last major Op's and stil have enogh juice for the rest of the week of back yard plinking. if you're in the market for a large type 9.6v consider this your best option

"Used this battery with a smart charger and it took like 2 1/2 hours, not bad.
I used it on my G&P M16 and the rate of fire was CRAZY. About 15 minutes into shooting, blew a fuse though ):
Pros
Heavy (compensates weight)
Long lasting
Good price

Cons
Sometimes too big to fit in other guns
Seems to blow stock fuses

"I am overjoyed with this battery! It can compete with a li-po battery. I use it in my ak with a matrix magnum motor and an m130 spring. This combination gives a great trigger response and ROF.

Pros:

- gives a great ROF
- can power and m130
- lasts a long time

Cons:

-none

"This is the monster of all batteries, its huge and great. Definitely a good buy especially when price is $45.00

"This battery will fit into the M4 RIS peq2 box. And pretty much all the PEQ2 box out there...

"TRUST ME! This battery DOES NOT fit in a PEQ2! I bought this battery with a KWA M4A1 R.I.S. AEG that came with a PEQ2 and it didn't fit inside it! This battery is HUGE! I had to saw my PEQ2 in halv an just tape the battery to it just so I at least had a battery on my gun xD I'll write another review where I note the measurements of it so you guys get a better idea...but this battery still ROCKES!!!!!!

"This is a "LARGE TYPE". Most airsoft sites will just tell you "Type" because it is standard for Airsoft.

Large types are for battery pouch (which this one is perfect), full stocks and some special hand guards that specifies to fit "large type".

It should say on your gun.

Most / ALL PEQ2 fits nun-chuck or small types or custom types for that PEQ2 box.

If your gun use large type, your life is much easier because you don't have to deal with all that battery accessories and exchanging battery is easy. However the guns are normally less compact.