Phillip,
Ok, 17 inch white, tan or red. The colour indicates the abrasiveness of each, so you need the softest ones, white is the softest, tan and red a bit more abrasive, get all three and then lubricate both the carpet & the pad first and give them a whirl, but do it on your own carpets first so you can experiment and find the one that gives you good agitation without damaging the carpet. You should never use dry pads no matter the colour.
Simon