The Universal ATR is an excellent general accessory for the analysis of solids and liquids, producing high quality spectra through the use of a pressure arm, allowing for good contact of the sample with the diamond/ZnSe crystal. The Spectrum 3/Frontier system ships basic transmission mode functionality (sample holder) as standard. There is a wide range of PerkinElmer sampling accessories available for the Spectrum 3/Frontier instruments. For the widest range of MIR applications, we recommend the Spectrum 3/Frontier UATR Accessory.