UPDATE:This has been tested and does fit on the 40 oz wide mouth but seems to be too loose on the 32 oz wide mouth, working on a 32oz version now.
Protective sock printed in TPU for any wide-mouth hydro flask. You have to print this is in semi or full flex filament as the tolerance is extremely small. I drew this up in fusion 360
Printed in black Sainsmart TPU at 20mm/s