• by Nina Lentini  @Nina_Lentini, April 12, 2007

Last night, KFC aired a national TV ad for its new Boneless Variety Bucket in which it placed a sound you might have missed, especially if you are over 30.

Only people under the Big 3-0 are expected to be able to hear the Mosquito Ringtone, a frequency of 17.6kHz, since hearing deterioration begins at 20.

The Mosquito Device was invented by Howard Stapleton of Compound Security Systems and is now a popular ringtone among teenagers who don't want nearby adults to hear incoming cell phone messages.

KFC is offering $10 Boneless Variety Bucket gift checks to the first 1,000 people who tell the Louisville, Ky.-based company, via its Web site, where the tone was embedded. It's just another way the company is working to keep viewers watching its ads.

In January, it aired a one-time-only spot during "American Idol." The first 10,000 viewers who ID'd the spot at kfc.com won coupons for free Buffalo KFC Snackers.

Last year, the company caused a stir by embedding a promotional message in one of its spots as a way to combat DVR ad-skipping.

The press release announcing last night's ringtone ad appeared directed to moms, who KFC has been targeting through its Bring Back Dinner campaign. In it, James O'Reilly, KFC CMO, says the company is "committed to finding new ways to engage Americans through their television sets ... and ultimately rewards people for paying attention. We call it the '21st century dinner bell'."

KFC's agency is DraftFCB, Chicago.