TWSBI Diamond Mini features a transparent acrylic barrel and cap, with plastic grip section and piston mechanism.
TWSBI Diamond Mini AL features a transparent acrylic barrel and cap, but the grip section and piston mechanism are made of aluminum.The AL version also often has a slightly different aesthetic, with the aluminum parts being a contrasting color to the clear barrel.
The use of aluminum in the Mini AL adds a bit more weight and a different tactile experience compared to the standard Mini.
Roughly 1 inch shorter than a Diamond 580 fountain pen
