Upgrade list (compared to previous version)
1) Grip frontal section design change
2) rear gas regulator type sealing design
3) rear tail section added to grip to improve concentricity
4) grip shortened a bit
Upgrade list (compared to previous version)
1) Grip frontal section design change
2) rear gas regulator type sealing design
3) rear tail section added to grip to improve concentricity
4) grip shortened a bit