Okay so the colours didn't actually match the ones in the picture at the time - I see this has thankfully been amended on the product page, but I do like the ones I received which would be 4 sheets of ten different colours in total - white, bright yellow, bright pink, deep red, dark blue, black, dark green, bright orange, dark brown and dark purple.
The sheets are A4 in size, which is file paper size and therefore bigger than the squares I've been able to buy from my local market. For the hardcore crafters amongst us, the felt is quite thick, nice quality but perhaps not suitable for the more teeny tiny of sewing projects.