I apologize for the confusion.
The screw cap is designed for an additional 10 m extension cable.
If you put two cables together you can have 20 meters.
This is the product page.
We recently upgraded 10 meters of cable to outdoor grade. It used to be an indoor type, that’s
why you saw the screw cap. It is not designed to connect the power cord to the camera.
Thanks for choosing us – This is Steve from the support team.
I saw you have ordered 60W PoE extender. This PoE extender only can deliver 60W PoE++ extension while it uses with FASTCABLING 5720-74 95W PoE injector. We don’t guarantee it works with other 60W PoE switch or injector to provide 60W PoE++ extension. If you want a high power extension, the best solution is used with 5720-74 95W PoE injector. The below please find the products page. https://www.fastcabling.com/product/90-95-w-poe-injector/
The PoE extender can repeat PoE/PoE+ for all the standard IEEE802.3 PoE Switch and POE NVR. There is no need to be concerned while it works with standard PoE power systems.
Please let me know if you want to make any change.