Often called the "Avenger", or the "AK1 Avenger", the actual name is just AK-1. Avenger was the name of the company that sold them. The guns themselves were actually built by an aircraft-parts machine shop called "Akraturn", owned by David Gardner. The name "AK-1" is simply a shortened version of "AKraturn".

Unlike other clone-makers, Akraturn has some special connections to Montneel. They were one of the original parts subcontractors for Montneel back in 1992. They produced about 1,000 assorted parts, like barrels, and valves for the Icon-Z.

Akraturn was originally supposed to make all the parts for the Icon-Z, but backed put of the deal after months of delays. This made Bullseye, the distributor, angry and refused to pay Montneel. Montneel then refused to pay Akraturn, and as a result, Montneel went Bankcrupt in late 1992. This ended Akraturn as a Montneel subcontractor, which was a good thing since they were the primary reason Montneel went bankrupt.
David Garnders (of Akraturn) brother, Doug Gardner, also owned a machine shop called Protofab. He heard about Montneel closing from his brother, and decided to invest money to get it back in business, but using Protofab instead of Akraturn to manafacture parts, and Montneel was back in business

This ended Akraturn's involvment in paintball until late in 1994. They saw the Icon-Z rise to huge popularity, and still had the original blueprints. SO, they looked at other succesful guns on the market, and redesigned the Icon-Z completely, and introduced it as the AK1.

Here is the AK-1 compared to the later style Icon-Z1:

Many of the changes that Akraturn made are obvious. They include:
1: Longer breech, to help keep barrel stablized
2: Dual barrel locks, instead of one.
3: 3-position forward grip
4: Factory ported barrel
5: Removable feed-block
6: Extended site-rail.
7: Factory light-green anno.

Less obvious changes include:
8: Redesigned trigger to reduce wear
9: Stronger heat-treated aluminium.
10: Helicoils on all frame mounts

Here you can see the AK1 manafacturer plate. Obviously styled after the Montneel plate, in the same location and shape.

Here you can see some of the special featuers. Most obvious is the forward grip. A popular aftermarket option back then, but this was notable as the first gun that came with one from the factory. It was further notable because it could be configured into 3 different positions! Also interesting was that this gun used DUAL setscrews for the barrel, unlike the SINGLE used on the Icon-Z. It also features a removable feedblock before Montneel released one for the MegaZ. Also notice the fancy bead site.

Here you can spot some differences. First, the trigger guard is rounded, unless most clones which are squared. Less obvious is the extended site-rail, and beavertail site. Also notice the trigger pins have a different layout then standard Montneel/Clones. The reason was that Akraturn totally redesigned the trigger. You can also see thumbscrews used before they were featured on Montneel guns. Not visible is the steelcore helicoil threads solidly holding the gun together.

Here you can see the extended breech. It 3 inches longer then the Montneel guns. The idea was that the extra length helped stabalize the barrel better, but it creates compatability issues. In general, Montneel guns can use all AK1 barrels, but not all Montneel barrels will work in the AK1.
Despite all the changes, the AK-1 is still about 90% compatable with the Icon-Z. The main difference being with trigger parts and barrels. Otherwise, it still has all the characteristics found on a "Montneel-clone".
The AK-1 is generally regarded as the best of the clones. Notice it even has a side plate!

The AK-1 was originally distributed by NPS. All the major companies had Montneel clones for sale.
USI had the Eliminator. Taso had the Checkmate. PMI had the Boxer. However, NPS wanted a "cheap knockoff", and the AK-1 was rather expensive to make. So, after about 500 AK1s were sold, NPS dumped the gun, and instead had a chinese company make a dirt-cheap copy called the "Icon".

Akraturn instead decided to sell the gun directly from the factory. They never sponsored any teams, but instead sponsored the APL who used the Ak-1 as prizes in all the tournaments in 1996-1997.

During these years, another 500 were either sold, or given as prizes. But the volume was never enough to justify the cost to manafacture, and production ended in late 1997.

As of Nov-2005, Akraturn still has a large supply of parts of the AK1, and still FULLY supports the gun. I was told 2-3 guns still show up every year for repairs. However, they do NOT have any complete guns for sale because they ran out of receivers, and have no intention of making more.

Below is an AD for the AK-1. These were handed out at the 1996 World Cup in Pittsburg.