just picked up one of these and cant use it . not saying anything bad or whatever (because of that fact of not using it). reason is it does not have an adjustable stroke . the stroke is the same on any setting . it only adjusts the amount of needle tip coming out of the tip . so you can have 2mm hang but the actual stroke is only like 1.5 mm . it never changes . hope that makes sense . example ; tip of needle even with edge of tube tip , set machine at 3.5 watch the needle . it comes out further but stays out not retracting back to original spot that is even with tube tip . that would be stroke not just because you can hang em out further .you put machine on 1mm its not coming out past the tip at all soooo. i got a fancy 1mm stroke pen i cant use