After P49 went through our thorough testing, we made P50 and P51.

Both of these prototypes utilize our complete set of confirmed v2 components. Within a few months of launching, we have already managed to upgrade some of our components and suppliers.

With the making of P50 and P51, we learned that new component colors, and the change in manufacturing process details such as the plating duration of certain components, require us to change how we decorate the back side of the Cal 852.

With new components and old decoration tuning, P50 and P51 became a unique existence in our prototype lineup.