Similar in style to the Europa, although with a less pronounced transition from the upper to lower barrels, this is a small diameter pen.
Comfortable and well balanced the Callisto is a convertible pen. It is able to accept a Parker ® style refill or pencil mechanism. Operation is through a single twist mechanism. The refill is replaced by separating the lower and upper barrel's and then unscrewing the nib mechanism in order to remove the refill.
Lower barrel diameter - approx. 15/32"
Upper barrel diameter - approx. 9/16"
Overall pen length - approx. 5 5/8"
