RIO's Rock Grinder is designed to sink very fast and be a nice mix of buggy-ness and attraction. This euro nymph has a hot tag of floss and a CDC collar that both wave enticingly In the current The matte black tungsten bead and PT colored body help it look like the insects of the deep.
The following are the bead sizes per hook:
Size 12 - 3.8 mm
Size 14 - 3.3 mm
Size 16 - 2.8 mm