Let's go over what we're looking at here. The below Air Conditioner options are the different styles of A/C's that Dometic has to offer. Then below that are components that are necessary to complete an install, or to repair your A/C (more information can be found on the A/C product page).
Brisk Air II: This is a basic unit at an affordable price, this unit has a taller profile allowing it to take up less roof space.
Penguin II: This unit is the most common of Dometic's line, it is the lowest profile and has an aerodynamic look.
Blizzard NXT: Dometic's newest addition to their line. It's comparable to the Brisk Air II, however it uses high quality insulation allowing for a quiet operation and higher efficiency.
Under Bench: This unit is common in small trailers that don't allow for roof top air conditioners.