https://www.amazon.com/Convatec-DuoDERM-Extra-Thin-Dressing/dp/B000PQ735Y/ This stuff is awesome for road rash, though not sure how it is different from saniderm

I have the duoderm: https://www.amazon.com/Convatec-DuoDERM-Extra-Thin-Dressing/dp/B000PQ735Y/

You cut them to size and my box has been lasting forever.

I second this. Even the cheapest patches get really costly pretty fast if you're using them frequently. Cutting up larger bandages is definitely the way to go. I thought bandaid brand worked really well, but the adhesive was a bit too strong for my face. I always felt like it took off some skin (this was pre-tret). (They were perfect when I got a deep gash on my hand though. That thing stayed put through handwashing, showers, taking gloves on & off, etc., & completely sealed the wound.)

Duoderm is the classic medical brand for real (non-acne) wounds. I used to buy these on amazon & cut them up and they worked well. If you're going to use enough to make it through a whole box, these come out cheaper than the bandaid bandages even though they're on the high end for large medical grade hydrocolloids. There's 10 4x4 inch bandages per box for ~$20.

Dynadex is a good dupe for Duoderm. I switched to these b/c they're half the price and work just as well. ~$10 for ten 4x4 in. bandages.