CQC class is the classification for people who use small arms in close quarters situations. For those who don't know, CQC stands for close quarters combat. Sometimes variations on this are used such as CQB which means close quarters battle, but the general meaning is always the same. The CQC class has a tendency to be very fast paced and use a heavy amount of BBs. This is often the preferred style of speedsofters. CQC doesn't have a definitive range where it changes from assault to CQC but it is typically viewed as under 40 feet. This is different from the military which can be a further range simply because the increased effective range of real guns.
The preferred guns of CQC class ranges a lot. The majority, though, uses small compact guns such as the MP5 platform like the H&K Galaxy MP5K shown in the photo. Most of the time they have a similar build, they are typically extremely fast. This is where HPA has become popular due to their ability to increase speed to upwards of 40-50 rounds per second and sometimes higher.
Another style of rifle that is gaining popularity in the CQC world is the bullpup design. Bullpups put the trigger assembly in front of the firing mechanisms allowing the stock to encompass the gearbox giving the design an extremely compact build. This has become popular because in the same length, a bullpup can have nearly twice the barrel length of other guns. The bullpup shown in the photo is the FN2000 which is popular because of its compatibility with the M4 platform.
Another popular method of play is to use secondary guns. Some people prefer to ditch regular guns entirely in CQC and just use secondary guns such as GBB pistols. This is popular to use due to the tiny nature of such guns yet the effective range is often sufficient to work with in CQC environments.
The last popular gun type is the shotgun. This is popular because of new ability of 3 round bursts. You pump the shotgun once and fire 3 rounds. This causes an effect similar to high ROF (rate of fire) but typically uses less BBs. This style is often harder to use and can be easily viewed as challenging.
CQC apparel is extremely wide ranging due to the fact that very few camouflages are effective so people began creating setups that are designed after specific people or soldiers. Their "kit" could include special camo only used by a specific person even though it is ineffective just as a style element.
The main apparel that is somewhat effective cover is black due to the simple fact that the majority of CQC fields are indoor and mostly dark. When they are not, people will sometimes base their apparel on the environment.
One major factor in apparel is ammo capacity. Because CQC is known for using a high amount of BBs, players often carry many magazine pouches on chest or leg rigs to allow for longevity.