Stem-guided valve &Tri-arm seat features greater fluid flow than four-arm seats, as well as it features an extra wide metal to metal seal on the valve flange. The serrated upper surface on the valve gives a longer non-breathing seal between valve body and insert while the rigid seat cross-arms give greater strength and positive sealing.The strong, thick, valve knock off nut holds the insert tightly reducing flex and breathing which lessens the chance of foreign matter getting between valve and insert. Stem-guided valve & Cross-arm seat features an extra wide metal to metal seal on the valve flange. The serrated upper surface on the valve gives a longer non-breathing seal between valve body and insert while the rigid seat cross-arms give greater strength and positive sealing.The strong, thick, valve knock off nut holds the insert tightly reducing flex and breathing which lessens the chance of foreign matter getting between valve and insert. Tri-wing guided valve & Full open seat: Three-wing guided valves and full open seats features greater fluid flow than four-wing valves, the unibody forged valve features greater strength than traditional welded-wing valve. Innovative unibody valve design eliminates snap rings, plates or keepers providing reduced maintenance by snap-on valve inserts and easy installation. HNA makes two styles of Four-wing guided valves and full open seats which feature greater fluid flow through the full open seat. The full open seat provides easier valve maintenance and seat pulling, in valve-over- valve fluid ends. Innovative unibody Four-wing guided valve design eliminates snap rings, plates or keepers providing reduced maintenance by snap-on valve inserts and easy installation. This combination will handle lost circulation material better than most conventional style valves and seats while the seating angle greatly improves flow characteristics and the heavy-duty load bearing capacity greatly improves service life. The unibody forged Four-wing guided valve & Full open seat features greater strength than traditional welded-wing valve. Innovative unibody valve design eliminates snap rings, plates or keepers providing reduced maintenance by snap-on valve inserts and easy installation.