Suction dies hard verses soft

[Titanium]

I have been looking into getting a set of suction does for my Bergeon 5700Z watch opener. I see there is the 5700-52 set and the 5700-62 set one being made from hard Adiprene and one from soft Adiprene . Whats the difference between the two? Which is better of opening watches?

Thank you. 

[oldhippy]

I never had that opener but the ones I did have had both I thought the hard would mark but used correctly I couldn't see any difference. I think you pay your money and take your pick.

[vinn3]

in the world of mechanics:   suction tools are not used, maybe to spin a valve being lapped in.  i use a fat "o-ring" somtimes on a stuborn pocket watches,  back or bezel.,but, to properly tourque a thread - a wrench is used - properly.  "keep searching".  vinn