it's a sepp -- senn sor attached to a helm. >> it's a senn sore that can record acceleration. the devices were invented to tell you when you might have a concussion. hit count added a pitch count for the brain. once it heads to 20 gs, like a hard strap, any time you hit over 20 gs, it will count. the idea is to use this to help prap. >> any hit of 20 gs or more will be captured, the numbers. >> a study showed in my opinion-year-olds, one team had a hit count of 150 and the other 60, because they limited how they hit in practice. we had to teach the teams at 150 how to get there. >> you had to worry about someone who coaches teams, you have to worry about it in practice. games. >> and you want to teach them to tackle properly. the only way to teach them is to go through it. there's no hitting going on. so for me, there's young kids that love to play. i think we need to change the - start a developmental tackle football. where they don't play until they learn to tackle properly. i don't think a kid can put on a uniform and two weeks later become an efficient tackler. that's my c