When I think of a "custom razor", I think of a custom-made razor meaning that the razor was made from scratch to my specifications, whether they be very specific or very general. Strictly though, I think a "custom razor" is one in which the customer had any options regarding the razor itself. I think that is general customization

I customized my sandwich for lunch today by requesting turkey in addition to the menu specs for the sandwich. I wouldn't think of it as a custom sandwich though. hmm.