The metal X (2 wire attachment) is for dry trimming and so is the serrated blade. The straight blade is for wet trimming. I havent dry trimmed with mine yet but the wet trim worked awesome and was very impressed. I'll be doing a dry trim soon tho with it. I'm sure it works just as good. I'll find out soon. Purple Nuggets from Mephisto is drying with her sugar leaf on and a whole plant hang. I just chopped the fan leaves off b4 the dry to slow it down cuz its winter where I'm at and lower humidity than summer time so not trying to dry them too fast.