Bottle OPS Reactive Shooting Targets Offer a Fun and Interactive Target Shooting Experience. Bottles can be filled with your favorite liquid or substance to enhance the reactivity down range. All civilian calibers have been thoroughly tested against these absolutely rugged polyethylene bottles. Hang them with the included paracord or set them on a non ricochet surface like a wooden post or tree stump. Each bottle comes printed with a high visibility target to test your groupings on one side. The other side of the bottle is printed with popular game (Deer, Bear, Turkey) with vitals indicated in red. Who doesn't like shooting bottles at the range ! Now you can without out shattered glass and a mess to clean up using Bottle OPS.