It's supposed to 'REPRESENT'... a slide under a dead spa one size fits all kinda thing.
Say you've got 3 hoses.
One suction hose, one discharge hose, and a blower hose.
The skid mount option basically puts everything mounted so that you just put the package under the spa, hook up the 3 hoses, power, air controls (or digital topside in this case), and poof you're in business.
However I always recommend against such an option. More than half the time, the plastic skids assembled arrive with broken (insert random name of component here) parts - mainly because UPS is horrible at handling large packages like this - (we've come to think they use our boxes for football practice).
While the idea is a good one, getting an assembly like this to your house perfectly intact (as we build it), is a crap shoot.
You'd best be served by saving the money, and ordering without the skid ASSEMBLED.
Btw, the skid is nothing more than a plastic platform used to mount the pump, control and blower on.
If you can deal with 3 separate pieces, then that's the best way to go - and forget skid shipping, or the plastic mounting base - unless you really need and can use one.
Here's what a full skid mount looks like with the AP-4/SB-1000 spa control:
http://spapartsnet.com/Spa-Packs-Contro ... 1_2_1.html
Hope this helps.
