well it doesn't matter don't worry
No worries.So is it meant to be used (mainly) in kitchen?
Possibly. Garden?
Less likely but not impossible. Bedroom? Bathroom?
Possibly both.Can it be considered a tool like a kitchen knife?
No. I was thinking of S = a dull knife and U = sharp knife?
No.Is it something electronical?
S is, U is not.If not the latter...safe = safe in general or something that is "made" safer for children mostly? (E.g. laminated socket...)
Safe in general.