A jewelry store in North Liberty, Iowa, is offering a most unusual deal—a free shotgun to customers who purchase an engagement ring.

"Diamonds are a girl's best friend," Jewelry by Harold owner Harold van Beek told local ABC affiliate KCRG. "So say: I'm hunting deer, and here is a diamond ring, dear."

The official promotion rules require a customer to spend at least $1,999 on an engagement ring purchased before October 31, 2012. The customer will then receive a voucher for a Remington 870 shotgun that can be redeemed at local retailer Fin and Feather. A standard Remington 870 can typically be purchased for under $500, though there are more expensive options available, including those with accessories such as scopes. The Remington 870 is typically used for hunting and sport shooting but is also kept by some people as a means of home defense. The 870 is also popular with military and police organizations around the world. In the U.S. it is employed by the military, Secret Service, Coast Guard, Border Patrol, IRS and even the Department of Education.

"We hope people know about the crazy jeweler in North Liberty that does crazy things," van Beek said, preempting any criticism over the unusual offering.

"Fun is more important than anything else, we try to put some fun in it," he said, admitting that he originally got the idea from a jeweler in Georgia who had previously offered a similar promotion.

There are a few legal restrictions on the promotion. Anyone hoping to obtain one of the vouchers must be eligible under Iowa law to be a gun owner. Iowa is a "shall-issue" state, meaning gun owners can obtain a permit issued from a local sheriff's department after completing a state-sanctioned gun safety course in order to carry a concealed firearm.

Convicted felons and drug addicts are reportedly excluded from the offer.