Four sets of 12 NEXTflex™ Small RNA Barcode Primers, with embedded index sequences are available offering an improved multiplexing workflow and increased flexibility. This new automation-friendly format enables multiplexing of up to 48 samples. The ability to pool samples in an efficient way significantly decreases hands on time while providing robust data quality. The primer barcoding system utilizes a 6 nt index to differentiate up to 48 different samples on a single flow cell lane. 48 barcoded primers are divided into 4 different kits (A-D). These barcodes were designed to be used with the patent pending NEXTflex™ Small RNA Sequencing Kit.