9V Battery Connector holder with DC - Ktechnics Systems
9V battery clip with 5.5mm/2.1mm plug - Melopero Electronics
Plug Connector Effects Pedals | Power Cable Effect Pedals | Power Cable Guitar Pedal - 4 - Aliexpress
Chanzon 9v Battery Clip with 2.1x5.5mm Female DC Connector I-Type Plastic Holder and UL Wire Pack of 5pcs kit for Arduino,LED Strip: Amazon.co.uk: Electronics & Photo
9V Battery Clip With 5.5mm/2.1mm Barrel Jack | Just4Fun Electronics