I use the HB2 blades with all of my Headblades, including the MOTO and ATX models. Yes, I know HeadBlade says they don't recommend using the HB2's with the MOTO and ATX. It works for me though. After trying many times to use the Moto and ATX with the HB4/6 blades, I gave up because they would barely touch my scalp on the back of my head. I've had no problem with the HB2's on a MOTO or ATX. All of their blades, including the HB4/6's, are great.