What is silk twill? 

Silk is a natural fiber, produced by silkworms.  Silk twill refers to the weaving process.

Twill can be identified it's the iconic diagonal rib created by the way you pass over weft and warp threads when weaving, as opposed to a satin or plain weave. This technique gives a very sculptural structured feel, while retaining a great drape.  It's lustre and durability make it ideal for wrapping, as it can hold a sharp and crisp knot when wrapping.

What does Momme indicate?

Momme (pronounced moe-mie, abbreviated to mm) is a Japanese form of weight measurement used to describe the weight, and hence thickness, of material.  A higher momme indicates a heavier, stronger, more durable silk which can hold its shape when wrapped or knotted.

Artful Pea wrapping cloths are 12 momme weight, heavier than your typical silk clothing to ensure durability so they can be wrapped time and time again.