Halo

Name: Halo (no not the video game)

Looks: pretty much a c looking shape with a dot in the middle.

Effect: In a near death experince the halo will grant Daisuke a massive Rengeration and will fully heal him but this take half an hour
to do. It can also give him a half healing regeneration but will only heal half of his cuts.

Drawback: The only drawback is that is it Daisuke's weak point.

Duration: As long as Daisuke is alive.

Cooldown: The half healing takes a half an hour to be used and a full two hours for the massive Rengeration to be used again.

There are a lot of things wrong here.

1) This isn't going to work because it would always bring him back, making him invincible on some level even if the invention itself could be destroyed. So that alone is an auto-deny.

2) That drawback is not nearly big enough for what you are requesting.

3) Cooldowns cannot be time. They have to be posts.

4) A fullbody regeneration that is an INVENTION requires extensive knowledge of the body and it's functions as well as how the body heals itself. This is because I am assuming Daisuke invented this, he would need extensive knowledge on the body and it's healing process. As such, you would need to write up something explaining how he found out about this whole thing.

5) Daisuke is a lone Shinigami. He doesn't belong to the Soul Society at this current point in time. The materials needed for inventions (let alone an invention that can restore one's body to full health) would be impossible to come by. The Shinigami technology is ages ahead of human technology. And I doubt humans just have technology of the level you're describing here just laying around...let along laying around with instruction for Daisuke to follow.

6) The machine cannot heal you AND grant you powers to heal yourself unless it was a unit of some sort that was apart of you, which again leads me to point number 2.

All in all, I have to deny this unless you can come up with a legitimate reason as to why you feel you need this, and are able to write up something describing the following:
*How Daisuke figured out how to put it together and make it work.
*How Daisuke learned so much about the human body.
*How Daisuke found the parts.