Laser Challenge, in it's most basic and cross-compatible form, has a front and back sensor that keep score of how many "hits" have been landed, and a blaster. There's no teams settings, no blaster-to-sensor recognition, and a LOT of wiggle room for other light sources (indoor lighting, sunlight, TV remotes) to interfere with things. Also, because of the nature of a torso-based sensor for players to aim at, it can be a little tricky to hit your opponent. Shooting around corners with no sensor on your blaster, taking cover that's higher than your waist, heck even just taking aim with both hands can make it a bit of a pain for people trying to tag you out to... well... actually do that.
I stole the idea from Mike Yates of Custom Tag Dynamics. He had a similar setup for his Laser Tagging group with a Laser Challenge V2 sensor rigged onto ALICE straps that he wore into combat. As such, my first in this lineup was the CVP-01, a Laser Challenge V2 sensor integrated into a Universal Shoulder Holster (USH). Not only did the -01 make me easier to hit for my opponents, but it also carried a few simple items like flashlights or a small sidearm backup pistol.
Later, I tweaked the design. Instead of a simple front-facing sensor, I modified the design by adding a dome sensor to the front, allowing for a greater range of angles to land tags on me. The CVP-03 was probably my most thought-out system. MARPAT Camouflage, Domed sensor, integrated tactical light system, it was great balance of adding a tactical advantage without adding too much weight, while still making myself easier to be hit. However, the CVP system would eventually go the way of the Dodo, as I set my sights on making something that could be added onto any system, something much more versatile and modular.
The Custom Sensor Setup, or CSS, was the answer. These systems, unlike the CVP, could attach to just about any harness. From something as simple as suspenders to something as complex as a full-on MOLLE rig, the CSS design meant I could use one sensor array on any tactical loadout. Unfortunately, with this modular setup, the system's reliability took a hit. The first two units, the CSS-01 and CSS-02 only lasted about a month each before their fragile internal construction broke down. Design changes in the -03 and -04 addressed this issue and saw continued use through the rest of the OLCA's history.
Because of their design, I've been able to use Laser Challenge systems on just about any setup. It's most commonly paired with my MOLLE rigs, as I tend to carry a lot into the field these days. First Aid kit, flashlights, spare batteries, a small screwdriver, radios, and other useful equipment generally go with me. Both the -03 and the -04 were also designed with the speakers facing my rear, making these excellent "pointman" vests. Although it's a little tricky sometimes for the user to hear when they're hit, it's a quick warning to folks following me to know when to take cover/identify the source of the incoming fire. I often lead from the front anyways, so this design suited me well.
The -04 was so easy to mount that I managed to pair it with my Captain America costume for our Halloween Game in 2011. It utilized two hooks on the costume to mount on and meant that I didn't have to cover up my costume with some kind of vest. I still use the -04 on my rig whenever we use Laser Challenge gear, as it's tough design has managed to last the past 2 years problem-free.
Below is a video of how the last of these custom Laser Challenge sensors functions. It's an older video, so bear with me!