Basically a lesser rating of gear absorbs a higher rating of gear. Ex: you have a 250 scout rifle. You press triangle and click infusion. A notice will pop up showing what gear can be infused. So you infuse a 280 pulse rifle into the scout rifle. Now your scout rifle went from 250 rating to 265 rating.

Wow that's so lame! A 280 weapon put into 250 turns into 265?! Man that's lame, do you know how the numbers work? If I put a 260 into a 244 armor?