Very Fast shipping and very good quality; The size of the charter is very practical, because of its "credit card" format. Mat, matte texture (no reflection) standing in a shirt pocket it is extremely easy to implement (although this involves small well collimated, eg with a 24-120). I did some tests in "yellow" environments (compact fluorescent and incandescent lighting mixed) and the result is "nickel", and avoids the recovery of the balance in DxO (which is sometimes difficult without any reference). In conclusion, very good product to recommend.
Kaavie - gray Charter set for white balance (3 cards: gray, black, white) - Credit card format (plastic)