CAD modeled in OnShape specifically for the older Olight S10 Baton, this diffuser measures in at 2.25" tall, .052" wall thickness, .960" outer diameter and .908 inner diameter for a snug fit, so it wont fall off the flashlight. Print it out of white, red or even green PLA, it's perfect for everyday needs and even camping. That's what I printed mine for, so I didn't have to by camping lanterns! Please enjoy and remix it if you want!

Side note: If it doesn't quite fit to your liking, lightly heat the open end with a heat gun on low while turning the part. When the part warms up and becomes malleable, then fit it to the light. Let it cool on its own and it should loosen a little. Fast cool it with cool tap water to shrink it. Alternatively, you can lightly sand the inside of the open end of the part with high grit sand paper, until the proper fit is achieved.