http://www.ebay.co.uk/itm/PECTIN-POWDER ... %26ps%3D54
Ummm, well you see, it is not that easy.
There are different types of pectins available for different types of product. You have the Brix and the Ph to look out for as well.
So you will get it wrong, I have been making Jams for 15 years, many of which in a business, and I still get it wrong. The good thing is, the Jam either sets hard, cook with it, or doesn't set, so you boil it up again and add more.
Maramalady in here is very good source of practical advice on this I think.
I have not used the stuff above, I got a big lot cheap from approved foods last year, but it should all do the same thing?
Sorry not to be of more help, but as I say, Jam Sugar, is just sugar with this added to it ( make sure you do mix it with the sugar first, as if you add it straight, it goes lumpy)