Having done this recently on my RX-7 I can confirm there is NO difference between the ABS and non-ABS master cylinders. The only difference is connection used at the front port. ABS cars use only two ports so the front fitting is a simple banjo fitting. MC's listed as being "w/ ABS" typically will come with this banjo fitting. Non-ABS cars require three ports and use a fancy double banjo fitting on the front port. MC's listed as being "non-ABS" don't come with this fittings as it has to be reused or purchased from Mazda. So for you Protege guys you can purchase either MC as long as it's for a '93-95 car but if you get the non-ABS version, which is usually cheaper, you need to reuse your banjo fitting.