Introduction So I saw somebody mention that this gun was getting a little popular for newer airsofters. Personally, I own this gun, and so do three of my friends that I play airsoft with. That's why I decided I should do a small guide, considering there isn't that much information out there about this gun. The summary is at the bottom of this post in case you just want that. Note: I got mine refurbished, so there might be slight variations. For the most part, though, it should all be stock. Gun specifications Length: 725mm-795mm, Adjustable Muzzle Velocity: 340 FPS with 0.12g BBs Fire Modes: Semi/Full-Auto, Safety Package Includes: Gun, Magazine, Battery, Charger Battery: 7.2v 650mAh Small Type recommended (mine is using a 8.4v 650mAh) Hopup: Yes, Adjustable Gearbox: Polymer gearbox Manufacturer: Umarex (made by Double Eagle) Licensing: Yes, H&K Gun description (outside) The HK416 is about $90 new for the gun with an adjustable stock, 7.2v 650mAh battery, high capacity magazine, and wall charger. Considering its lower FPS thanks to some of its plastic and weaker internals, it falls into the "medium powered electric guns" category, or MPEG. The whole body is black polymer, and it's made as two halves of a shell. On the right side it has a mock forward assist, as well as a dust cover that can be opened to reveal the hop up. It also has the magazine release. Picture of right side of gun The main thing that's unique about the left side is the selector switch. The HK416 has safe, semi-auto, and full auto modes. Picture of left side of gun This HK416 has a top rail, two side rails, and a bottom rail. That leaves lots of room to attach whatever you want. Up until now, everything I've been describing has been plastic. Luckily, the gun has pretty nice iron sights. The rear sight can fold down (like in the picture) and is mounted to the rail. You can turn the knob to adjust it side to side. You can also rotate the inner piece to change the hole size. The part that mounts the sight to the rail is plastic, but the piece holding the sight itself is metal. The front sight also folds down, and it's completely metal. It can be removed with a screw on the right side. The HK416's stock is adjustable, as you may have noticed, and it has several positions it can lock to. The back comes off so you can put a nunchuk style battery inside. On the stock is a place to mount a strap. On the front of the gun there's a metal mount point on either side for the strap. Stock with back taken off Gun description (internals) The worst thing about this gun in my opinion is the gearbox. It's a version 2 gearbox, though it has a motor cage which is uncommon. It's not quite standard, and since it's mostly polymer there is barely any room for improvement. It can, however, run on a relatively weak battery. The gearbox shell is polymer, as well as the gears. I'm calculated a gear ratio of 48:1, but since that number seems too high I may have messed up with counting the teeth or with the math. I'll leave a table of ratios at the end of this paragraph. The motor works well, at least with the stock parts. Most of the other stuff is what you'd expect to find in any gearbox. (Thank goodness the spring isn't plastic!) Since the HK416 does 340 FPS the spring is probably a m100 or close to that. The outer and inner barrels are both metal. The hop up unit is plastic, and seems okay. Gear ratios: Pinion:Bevel = 12:48 Bevel:Sector = 10:40 Sector:Spur = 12:36 Polymer gearbox Outer barrel Hop up and inner barrel Where to buy You can buy this gun from Evike, Amazon (if it's in stock), or ManstoreHQ. You can probably buy this from the Umarex store too. $70 refurbished- https://manstorehq.com/collections/airsoft-aegs/products/refurbished-hk-416-airsoft-aeg-includes-magazine-battery-charger-and-bbs Out of stock new- https://www.amazon.com/Heckler-2279042-Black-Electric-Power/dp/B00BLQZZDY/ref=cm_cr_arp_d_product_top?ie=UTF8 $95 new- https://www.evike.com/products/39971/ Summary Even though many parts of this gun are cheap, I think overall it's decent quality for the price. I use this gun for in the woods to fight my friends, and it's served me well so far. The gearbox is polymer, so even though it performs very well at the level it's designed for, said level is too low for many people, and there's barely anything you can do to upgrade it without replacing the gearbox entirely. The hop up isn't amazing from what I can tell, but it works okay. The body is pretty strong overall, and has a good amount of features. I don't recommend this gun if you are going to go hard on it, play constantly, or plan on modifying it. If you buy this gun, however, it should serve you well enough until you decide to spend money to afford a better AEG. Edit: Guges corrected me, it's not a LPEG it's a MPEG. Also, the P is for power, not price. Edit 2: Replaced "The gearbox looks a bit like a version 3, but the motor mount does not come off, and the shape is a little different." to be more accurate. Thanks peeque. Edit 3: Added a little bit more info from Dead_Christmas, check out his post if you have a chance.