Which RNA types can I expect in the small and large RNA-enriched fractions?

The SPLIT protocol provides you with a size cut off at ~150 nt. The small RNA-enriched fraction (<150 nt) will contain miRNA, tRNA, 5S rRNA, and 5.8S rRNA, while the large RNA-enriched fraction (>150 nt) will contain mRNA, 18S rRNA, 28S rRNA, and snRNA.