Spanx TYT Replacement Thinstincts Low Back Slip (Very Black) Women's Underwear. The best base layer! An updated take on a fan-favorite we re-engineered this style with added performance features like breathability wicking and absorbency and added convertible straps so you can wear multiple ways- the perfect lightweight layering piece! Support level: Smooth. Thanks to convertible straps this slip can be worn standard halter #Spanx #Apparel #Top #Underwear #Black