Description General description Pipetting needles are available in a wide choice of sizes for use in laboratory procedures. All needles are made with type 304 stainless steel cannula. Catalog numbers CAD7950 to CAD7957 needles are fitted with stainless steel hubs for special applications with corrosive materials or critical procedures. Catalog numbers CAD7930 to CAD7942 needles are fitted with standard nickel plated Luer hubs. These needles are used in conjunction with both manual and automatic volumetric dispensers, dilutors, and pipettors.