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"This is the chronograph I use and it is an excellent step up from other, more traditional models.  The first chronograph I ever used was when I was a kid, the old shoot-through-the-sticks type model - it was my Dad's. The *very* first time I got behind it, I put a bullet hole right through the guts of it!  Dad was pissed to say the least!  I had CRPTS (chronograph related post traumatic stress) from that day forward until the day I started using a Magneto.  They are super accurate, reliable and you never have to worry about shooting a hole through the center of it!"   - JSharps  

The MagnetoSpeed Sporter chronograph kit was designed to be used on barrels from 1/2 inch up to 1 inch in diameter. In can also accommodate muzzle brakes, flash hiders, etc, up to 2.7 inches in length. Ideal for contoured rifle barrels (sporter barrels).

MagnetoSpeed Sporter features:

• Simple, one-button cycling display (shows recent shot velocity and statistics, plug in to turn on)
• Battery : 9-Volt (included)
• Easy access battery compartment, no need for screwdriver to swap batteries
• Three sensitivity settings for fine-tuning
• Integral, quick-attach strapping system; with metal buckle and triad thumb nut
• Proven technology with updated sensor design
• Integral 3.5 foot sensor cord

Kit includes:

• Display Unit
• Bayonet-style sensor (Bayo)
• Thick and thin rubber V-block spacers
• Heavy duty strap with thumb nut tightener
• Ultra-compact storage container.