I decided it was time to up-grade & replace my Shooting Chrony with a new Competitive Edge Dynamics CED M2. The Shooting Chrony has given me a couple of years with out much trouble or a scratch on it. Seventeen rounds with a 17 HMR Saturday afternoon to try the new CED M2 & I hit the front sensor. Crap! Midway has replacements. I guess I'll order two in the morning.