Piston ring question
 

I'm looking to change my piston rings. The OEM thickness is 1.2mm for first ring, 1.5mm for second, and 2.0mm for oil. I want to put in Hastings rings since they have the waffle style oil ring, but per their tech sheet the 2nd ring is only 1.2mm instead of the 1.5.

Anyone know why theirs would be thinner, and would there be potential problems from installing a thinner ring?