Boppy Soothing Slipcovers - Boppys are kind of shy. Give them something great to wear. Boppy® Slipcovers are machine-washable and fit every Boppy pillow. So it’s easy for moms to keep things clean, even with babies new to this whole eating routine who may have a accident or two. The Boppy Soothing Slipcover is made of the softest, most luxurious boa fabric.