Save the masks and elbows
This stencil has two parts which you should save and use. 1. The stencil. and 2. the masks. Also save your pieces of plastic from the elbow holes. These are tiny and hard to keep track of being transparent, but you'll need them to make your projects look good.
I wish the plastic was a little thicker and I find that 6 x 6 is too small a size. I wish it was 8 x 8".