A nice touch is the bright ring around the Emergency Stop Module, helping you locate it fast.
4-pin 40/30Amp 12V DC Waterproof Automotive Relay with Heavy-Duty Wire
what stands out about this relay is that the label shows the brand NOVITA, which some folks will recognize.
You will find that the 70*20*18mm / 2.75*0.78*0.7" size works well in modular builds.
A nice touch is the way the Model 700-P400A1 sits flush in the panel, keeping things tidy.