I still need to make that blog post, but here's the patterns for the V3:
TOM BIHN V3 Mask Pattern - Size M/L
TOM BIHN V3 Mask Pattern - Size S/M
I'm glad you love your V3! If you haven't already, consider leaving a review on the V3 page; we're donating an additional V1 Mask for every review posted on our website for bags or masks.
The folks testing the V4 in Flannel love the 100% Cotton Flannel so much that we've decided to offer only offer the V4 in Flannel. I (and our other testers) find the flannel to be soft, breathable, comfortable, and it also gives the mask a nice structure. Since Nik gave me a sample V4 in flannel, it's become my go-to mask. I've worn it on hot (90-degree-ish) summer days and I don't find it any warmer than the other materials we use. Anyway, I hope you guys like it as much as we do!