slip Silk Headband The Knot in Black. slip Silk Headband The Knot in Black. The slip Pure Silk Headband features a lightweight knot design and a gathered slipsilk covered elastic back. The durable, super-soft, comfortable fabric helps keeps hair in place and out of your face while being gentle on your delicate hair.. In Black. Made from 100% highest grade (6A) long fiber mulberry silk with a thickness of 22 momme. Anti-crease & anti-breakage. Non-toxic dyes. SLIP-WU16. 857032008500.