The Metcal CVC-9CH0034S Rework Cartridge, Slot For Chip 1812 is for use with Metcal MX Series Soldering & Rework with MX-RM3E and MX-H1-AV Hand-pieces for conduction rework of surface mount components. The slot cartridges are used for the removal of discrete and passive devices. 900 Series for temperature sensitive applications.