One of several proteins that assist in the late maturation steps of the functional core of the 30S ribosomal subunit. Associates with free 30S ribosomal subunits (but not with 30S subunits that are part of 70S ribosomes or polysomes). Required for efficient processing of 16S rRNA. May interact with the 5'-terminal helix region of 16S rRNA. Monomer. Binds 30S ribosomal subunits, but not 50S ribosomal subunits or 70S ribosomes. Belongs to the RbfA family.