I have plenty of underwear, but don't mind adding a few sexier options here and there.  When I bought the Flashback Pro Boxer, made in the USA, I liked the look and wasn't aware of the buttocks shaping benefits.  Andrew Christian's innovative FlashLIFT design lifts and contours your derrire for those seeking the perfect bubble-butt.

The Andrew Christian Men's Flashback Pro 8"/ 20.3 cm Boxer has straps from the crotch to the side of the ultra slimming elastic waist band, like a jock strap, hidden in the seams to boost and shape the buttocks.  No padding or hidden cups are used in these form fitting 90% Cotton, 10% Spandex machine washable boxer briefs.  Plus, an accented, no-fly front pouch comfortably holds the goods.

I don't have much of a derrire, so the push-up effect of these boxers doesn't appear to do much at all.  Andrew Christian states "people can add up to 1/2 to 1 inches (1.3 - 2.5 cm) onto their current buttocks measurements helping them achieve a rounder fuller look."  Since I couldn't see a difference, I measured and found a half inch increase in my measurements.

The straps within the seaming creates a slightly thicker than normal seam.  When sitting for long periods, I found the straps to be uncomfortable.  The Andrew Christian Men's Flashback Pro Boxer would be more comfortable for a night on the town, but not so much for a day at the office.

If you're looking for underwear to create a fuller and shapelier derrire, the Andrew Christian Men's Flashback Pro Boxer is will create this effect and is worthy of consideration.  I'm not really interested in this feature and was just looking for an attractive pair of underwear.  I will wear the Andrew Christian Men's Flashback Pro Boxer, but most likely won't purchase another pair.

PROS:
Fashionable boxer brief
Comfortable most of the time
Easy to care for
Creates a shapelier derrire

CONS:
Thicker than normal seams in the back