Originally Posted by EAMotorsports
One thing I was going to add is the 5mm does make sense since electricity flows across the surface one would assume that 5mm is better than 4mm due to more surface area. But if we are not pulling enough current to exceed the surface area of a 4mm bullet do you really need 5mm?
The "skin effect" you are talking about will have no effect on the battery connection. Skin effect only becomes a problem with high current, high frequency AC circuits (Or pulsating DC Circuits).
The 5mm should offer more surface area, for a firmer, less resistive connection, but in real world, you will never notice a difference..
Pure advertising/marketing gimick.