The 135x16 is 1/3 the height of the eye longer from top of eye to top of shank and the point from the bottom of the eye to the tip is ever so slightly longer. I set up my two Adler's with 135x17 needles because they come in more sizes, titanium coated I can get in size #180 vs. #160 for 134-35. To use 135x17 needles, I have to adjust the needle bar ever so slightly. This way, I only need to carry one system of needle for most all my machines, i.e. Juki. singer, Adler.