Pioneer Vertical model has the highest thermal output and heat efficiency among other Vertical models.Thermal heat output of each panel is 3150 Kcal/hr. This model has the best balanced rate of water content and heat output. It can produce high amount of heat while save energy. It comes in 3 luxury and shiny colors. Black / Gold / White The caps of the Pioneer Vertical model have a ring part that distinguishes it from other models.