I never realized before that the tailcap of the D80 has the retaining ring contact the tube when it is tightened down, even though I have one. :+1: I had a look and sure enough it does. Several other lights I looked inside have the tube contact a machined face in the cap. The retaining ring is smaller and does not contact the tube body at all.
It seems to me that if they really want to make an improved version of the D80 they should redesign the tailcap retaining ring. No wonder some manufacturers like to glue parts together.
Then while thay are at it redesign the head to use a 17mm driver.
I like the feel and appearance of the D80, but the lights I use most have side switches which has moved my two D80’s to the closet queen shelf. Appearance was what made me desire the D80 in the first place.