The shinwoo light kits are BOSS! the coolest. Attaching them to your yo requires modifications though. I put the kits in my Night Moves 5 . first i had to find disposable cups that fit the wells of my yo (they dont weigh much and are transparent, and cheap). I have the lights glued to the caps and hold the caps to the yo with reusable adhesive putty.
as for the lights themselves amazing . when you you have a very fast bind the springs might get wedged on the battery, causeing the lights to stay on. but you can just hit it and free the spring. the colors come out in patterns of red blue and green. varying in speed from short bursts to long fades. in my opinion well worth the money. I have yet to test the battery life. i also dont know the battery size , or how easy/hard it is to replace the batteries.
any one know the battery size?