Lamy T51 ink comes in a 30 ml bottle. The T52 ink bottle holds 50 ml of ink. It also has the unqiue pullout piece of blotting paper. Very handy sometimes. The more recent addition was the T53 premium ink - Crystal Ink. The ten colours are very colourful. The bottles are smaller holding 30 ml of ink.
T53 is available in the following colours: Ruby (pinkish red), Rhodonite (lighter tone pink), Beryl (deep rich pink tone), Azurite (deep blue with some purple), Benitoite (a medium grey), Peridot (rich green), Amozonite (a turquoise), Topaz (red brown), Obsidian (black) and Agate (light grey).