The KUPO die-cast knob, featuring a solid steel 1/4"-20 threaded bolt on the front end, is designed to connect the FC15A and FC15B corner adapters. It securely locks the butterfly frame pieces together, making it easier to store and transport.
- Corner bolt to fix FC15A with FC15B
- For Kupo square butterfly frame
- 1/4"-20 threaded stud on the front end