InvictaPro Diver Stainless Steel Men's Automatic Watch - 42mm

what is the difference between the Invicta 29178 and the 30091, they look the same?

Invicta 30091 what movement does it use?

Does this watch have a battery?

How difficult is it to take out links to size the band? The couple of jewlers I taked to, said there a pain to size. Do they have the basic push pins?