interesting but I want to buy 8 and there is no option, they only seem to have one for sale 
In the listing he says:
“This is for one clamp , if you need more then message me !”
So you should be able to get the eight you need 
Yes I have a few of these , great quality clamps , I tried most clamps available from the cheap copy T-bolt ( lots of them are on eBay ) to proper Mikalor �13 T-bolt jobs but these are the best I have had , fit spot on with no nasty long bolts sticking out like when the T-bolts are tight , these are always tight no matter what the temp .
Message me if you want a full set .