This is designed to be printed in TPU and will not work will plastic filament. I made a few changes to my previous Session sleeve which includes more protection, a slightly beefier design and easier removal of the camera from the sleeve. Supports are not needed when printed as shown in the render. With a 40% infill it weighs 14.7 grams. The sleeve is not visible at all, even with SuperView.
A version without the strap slots can be found here: https://www.thingiverse.com/thing:2852274
My previous Session sleeve can be found here: https://www.thingiverse.com/thing:2112212