The "Critical Mass" sport pak from Trinity features the EP 3600 mAH cell which is based on the same technology East Power developed for their 4200 mAh M-III cells. Designed for higher voltage output and longer run time the EP 3600 is the most durable sport battery pack on the market. The internal resistance of the EP 3600 cell makes it suitable for all stock, 19 turn spec and milder modifi ed motors down to 13 turns. It is also suitable for all brushless motors.