This document provides a buyer's guide for RT2 Profiler PCR Arrays, listing the compatible plate formats and recommended RT2 qPCR Master Mixes for different real-time PCR instruments. It shows that PCR arrays are available in 96-well or 384-well formats to fit standard or fast block instruments from ABI, Bio-Rad, Roche, and others. The guide specifies the number of 96-well or 384-well PCR arrays that can be run with each master mix purchase. It also describes RT2 RNA QC PCR Arrays for validating RNA samples prior to gene expression analysis.