The guys at TheGearLocker.net have been checking out some of the protection equipment from PDI:
We have been very busy! This is our latest review of safety equipment from the company PDT, Practical Defense Training Technologies (www.pdt-tech.com). PDT makes equipment for simunition training, but there is a great cross over to Airsoft Training. If you are a field owner, referee, or for younger players, these items could be right up your alley.
http://www.thegearlocker.net/2012/02/pdt-protection-equipment/