Frank's Umbrella Corporation Is Designing a Kanban System

Short Answer

Frank's umbrella corporation is designing a kanban system. They know that they are expected to produce 100 umbrellas per hour. They've also determined that a key external resource takes 30 minutes to deliver the required material once an order has been transmitted. To start with they want to maintain a safety stock of 25 critical parts. Originally they want to start with 3 kanbans. What container size should Frank's umbrella company start with?