We’ve been making them since the beginning of the pandemic, the pattern is based on a store-bought one we took apart, and we’ve made several iterations over the years including making wearable versions. It’s sewn from an airtight fabric (silpoly is the best we’ve worked with, but hard to sew) on a normal sewing machine, and has a continuous fan to keep it inflated
I used “Saint Derelict” as a pen name for some poetry in high school, then in college I used it without the Saint as a character name in Numenera, and it stuck as a gamer name. I used it here because my other online handles are either unwieldy or name-based and I didn’t want a new one