Motor stab breakers are for our directional customers using straight blade mud motor stabilizers. Here at ChrisCo, we took into consideration sometimes 4 blade straights are needed and sometimes 5 blade straights are needed in your directional obstacles. So rather than spending more money on larger inventory for both 4 and 5 blades, we decided to make our motor stab breakers universal to handle both 4 and 5 blade straight stabilizers simultaneously. If you have a different requirement, let us know!