You can customize the holder (shaft) and refill (refill). Choose from 4 types of 3 color holders and 4 types of 5 colors. Mix and match with gel ink, oil based ink, and mechanical pens. Combination ballpoint pen; Ball diameter: 0.02 inches (0.5 mm); Color: Red; Length: 3.9 inches (98.6 mm); Art Supplies Shop Dot Com Postcard A: Limited Product!! 1 x Cute Animal Postcard