Various companies have used this type of loading, such as [[Columbus]], which patented a version in 1929 ({{Cite patent|GB|334913}}), but in general it introduces unnecessary mechanical complexity and greater stress on the materials of the pen, without providing any particular benefits. It has been adopted mostly as an attempt to circumvent patents on [[lever filler]], or as a sign of distinction with respect to other mechanisms, as it avoids the side slit for the lever, but has never been a significant success.<noinclude> | Various companies have used this type of loading, such as [[Columbus]], which patented a version in 1929 ({{Cite patent|GB|334913}}), but in general it introduces unnecessary mechanical complexity and greater stress on the materials of the pen, without providing any particular benefits. It has been adopted mostly as an attempt to circumvent patents on [[lever filler]], or as a sign of distinction with respect to other mechanisms, as it avoids the side slit for the lever, but has never been a significant success.<noinclude> |