Beauty sleep, but make it lash-friendly. This ultra-soft silk sleep mask features a contoured design that gives your lashes the space they need. Beauty sleep, but make it lash-friendly. This ultra-soft silk sleep mask features a contoured design that gives your lashes the space they need. Proudly Australian and family-owned, Slip is renowned for its luxurious silk pillowcases and beauty products, crafted from the finest quality silk to elevate beauty sleep and minimize friction on skin and hair.