Review on DuPont FlexWrap NF 9-inch x 75-foot - Self Adhesive Butyl Flashing Tape - 1 Roll by Daniel Shankle

Good stuff. It's so expensive, even though I only wrapped the bottom corners of the window openings with regular membrane for the rest of the length. Pros: It allows you to stretch the corners of the lower window openings. Glue is the best I've used. holds up much better at marginal conditions compared to e.g. Grace Vycoor Cons: very expensive (I set 35 windows) I couldn't fold wrinkle free so it doesn't lay as flat as ideal