Couverture is essentially a version of chocolate primarily created for chocolatiers or bakers to make other products out of. However, for anyone serious about their chocolate the opportunity to purchase their favourite bar in a more economical form is very attractive - especially when you can save as much as 50% to 75% off the retail-packaged price.
There various forms of couverture. Some companies will produce chocolate in disk or button form, others will produce it in a lozenge form, others will create large 1kg slabs of chocolate whilst others will create smaller bars but package them together, whilst others, still, will produce couverture bars slightly larger than normal bars - which are aimed at chocolatiers to test with.
Often the final finish won't be as shiny, glossy or 'polished' as the traditional retail form, but if you are buying for yourself and for the flavour in particular you will most likely not be too interested in the physical appearance of the chocolate.
The positive side of buying chocolate in bulk is that it should also last a great deal longer than retail bars and you will typically save a great deal on delivery costs too.