English: From top to bottom: Lamy Z 10 proprietary ink cartridge, Z 27 converter and Z 28 converter. The T 10 fountain pen ink cartridge has approximately 1.15 ml ink capacity.

For using bottled fountain pen ink Lamy offers several proprietary piston operated converters. The Aion, Accent, CP 1, Dialog 3, Imporium, Linea, Logo, ST and Studio fountain pens can be fitted with the proprietary Z 27 converter for the premium line of fountain pens that has approximately 0.7 ml ink capacity.

The ABC, AL-star, Joy, Nexx, Nexx M, Safari and Vista fountain pens can be fitted with the proprietary Z 24 or Z 28 converter that has approximately 0.7 ml ink capacity. The converters for the school/young writing line of fountain pens feature two protrusions that form fit into two arresting recesses in the grip sections of these pens.