BAM! Kim Kardashian and Kylie Jenner decided to become walking billboards for Kanye West's new Yeezy line and gawd, what some free publicity can do for a clothing label!

No need to hire supermodels, the Kardashian-Jenner girls are the best mannequins when you need someone to strut their stuff in body-con Spandex. And really -- who's got more severe curves than these ladies? The photos are practically 3-D with those bodacious butts just bubbling out at you!

Kanye West must be single-handedly keeping the Spandex company in business, using the fabric in literally every piece of his new line. Tight pants, tight tops, tight pointed-toe ankle boots -- tight, tight, tight!

We snapped the girls at Kanye's Calabasas office, coming in and out of the building in different looks, clearly hoping someone would be there to photograph them. They posed in a huge 4x4 Jeep, showed off lanky legs in thigh-high boots, and Kylie slung a hip pack over her shoulder for a trendy look.

Question is, who'll wear this stuff other than Kim and Kylie?