This poster compares the volumes of sample solutions delivered by an array of stainless steel and hydrophobic-coated pins as measured by a fluorescent-dye approach versus a dual-dye absorbance approach. The V&P Pin Tool array was used to deliver aliquots of both aqueous-based and DMSO-based FITC sample solution into test plates under controlled experimental conditions. The same testing was conducted using the dual-dye absorbance approach implemented by the ARTEL Multichannel Verification System (MVS). Each measurement method was tested side-by-side on a series of pins capable of transferring from 20 to 315 nl. The effects of solvent composition, dye concentration, and source plate volume on actual delivered volume were compared for each system. The MVS based assays and fluorescence-based assays resulted in good general agreement. Areas of divergent results appear to be due to dye concentrations effects on the liquid surface tension or solvent/dye composition. Theories explaining these results are discussed.