This thing is awesome. Fits my TM P90 TR like a glove. It has the same thread size as the ECHO 1 tracer unit, so you can put it on another brand gun. BBs come out much brighter than the ECHO 1 tracer unit. After putting about 1000 rounds through it, it started only flashing every other BB, and then every third and then fourth BB. I was seriously considering returning it. The I changed the batteries and everything was fine. Apparently as the battery gets lower the sensor is less sensitive (due to design or lack of power) and would only sense a BB flying by once in a while. Also, its really easy to forget to turn it off because the switch is very small. You know its on when, the white band on the switch is not visible, and a faint red light can be seen inside the unit. All in all, a great buy.
-BBs come out bright!
-On full auto it looks like your gun is shooting a laser beam
- Takes 4 AAA batteries (and not some watch battery that you never have on hand)
- Looks and feels like a real silencer (be careful walking around in public with this on your gun).
-The instructions are not in english. So you better be good at deciphering the little cartoon pictures they put next to the japanese/chinese.
- The threads run in a different direction than you expect. Its Lefty Tighty, Righty Loosey. I forget this every time I put it on. But this is the case for all tracers units that I've seen.
-Price, you can find it cheaper elsewhere, but you'll probably pay more in shipping. Make sure to shop around.