I love the new threaded motor retainers from Estes. The one important possibility is the ability to recess this in to the rear of airframes that desire a flush profile appearance. This tool is designed to be used for such an occasion. It is only useful with recessed mounts of a maximum 1 inch depth from the aft end of the airframe tube. Minimum width allowed for wrench clearance is the inside diameter of BT-60 tube or 1.595 inches, or greater. It has holes to make an optional fulcrum arm ( wood dowel ) for ease of twisting. Can work with BT-60 fin units in my shop where applicable. I hope you guys like it!
UPDATE: New! I now offer this tool with PA12 plastic as it has more robust mechanical properties.