Okay, so I bought a binding machine off ebay... works FINE... all's good... but I'm not sure what this one knob does... and what size combs to buy so I thought I'd ask on here. I emailed one lady at acco, for advice, but that may take a while and I'm an impatient cuss. Here's the link to the listing.... http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=380235236072&ssPageName=STRK:MEWNX:IT The knob on the left of the machine controls how far the binding combs are opened... that I get... numbered 1-9 I think it also controls the margin... how far from the edge the holes are punched. But I have no idear what the knob on the right does... it's got boodles of fractions on it. It can't be the hole punch size... as those are metal rods that are 5/16ths rectangles... I know which controls opening and margin... so what the heck else is there?? REALLY lost on that one, but since it works as it is I don't think this is all that vital. Also, some verification that the combs I need to buy have <5/16 "posts" is good... Are ALL combs designed to fit these 5/16th rectangles.. so the numbers you see ONLY apply to the diameter of the coiled comb? I'd hate to order some and them turn out to be useless... I think I've got that right... That the numbers... 5/16....3/4... are diameter and thus how many sheets will fit on that comb... Though, why don't they just bloody say 20, 40, 100... why do they do this fraction stuff and risk this confusion... ANYWHO, any advice appreciated.