Using an ATN 1500 auxiliary ballistic laser is not that expensive and really worth it. And seriously, I didn't think it would be worth so much for its price. Not long ago I didn't even know about the ATN company, but after I found that they have laser rangefinder I was more interested in them. $349 for a digital rangefinder with whom you can hit a target at 1500 m it's a small price. It's simply connects to your mobile by Bluetooth that give you more comfort than ever. Ah and here is a version for 1000 m, it's cheaper but have the same function ability.I use an ATN Auxiliary Ballistic Laser 1500 it's not so expensive and it's really worth it.