BH Half Back - Bead Head. The Bead Head Half Back Nymph is a pattern that has stood through the ages of time. A very 'buggy' look to this fly gives it the ability to still be strong even when the modern, more 'real' looking flies fail. The Beadhead Half-Back is the fly that all the veteran fly fishermen keep on hand at all times for those particularly difficult days. A real recovery master.