The unit comprises of a large reservoir of ink (100mls of each colour) that sit outside your printer. Attached to the reservoir is a set of silicone tubes which feed into special cartridges which you use instead of your current cartridges. The printer works exactly the same way but now you have 100mls of each colour rather
than 10mls (which is the contents of the average cartridge).
Even better, when you get low on ink, just pull out the plug on the reservoir and pour in some refill ink.
Best of all you are saving up to 94% compared to the cost of cartridges.
Obviously, the more you print the more you will be saving.
Consider it this way, The Canon BCI-6 colour cartridges have approximately 13mls of usable ink inside while the BCI-3eBK has around 25mls. Canon BCI-6 cartridges retail for around $29.30 each and the BCI-3eBK is about $24.75 (prices correct as of Jan 2014 via officeworks online*)
Rihac CISS is prefilled with 500ml of Rihac ink and is equivalant to approximately 31 Canon cartridges which would cost you about $1007.00 to purchase seperately.