The EM-01 is the smaller of the 2 EM radiators. EM is made by New Line in Italy. The difference is the EM radiator is machine MIG welded not hand TIG welded. This process is a lot faster. Also the core is not the racing core used in the New Line RS,BIG,R-OK radiators.
The EM is perfect for the hobbies driver who does not want to spend $800 on a radiator.
New Line as introduced this radiator so you dont have to go out and buy a crap radiator from China or India.