Bonus Block 10 titles Triple Play is our last bonus block and it's three for the price of one!
I made the Block 1 version of this block and used toweling for the C squares.
Make sure you cut each square from the same section of stripe, so they are symmetrical and the stripes match. This is only important if you are using large scale stripes, like me, or if you are using a very obvious stripe. If they were tiny pin stripes or and narrow ticking I wouldn't worry about the symmetry.
This was a fairly straightforward block to put together. My fabrics were starched and they sewed up like a dream.