This panel mounts are made of solid plastic, they are not lockable, but contacts are tight enough to hold horizon and top placed XLR plugs. Going to use them for stationeer distribution box.
Neutrik NC3FPP Chassis Panel Mount XLR Female socket
Excellent connector for the price. All terminals clearly marked. Easy to mount either through a panel or behind. Accepts solder with no problems. Basically it's NEUTRIK quality. Well done proaudioshop for supplying these at at great price and quickly.