I had to join some ethernet cables under the floor in the house. Not ideal as I would have preferred to re-run the cable but sometimes you have to work with what you have.

I didn't want the cables coming out once the floor was back down so the holder lets you cable tie the joint / coupler in place along with the ethernet cable.

The ethernet jointers I bought were these ones: https://www.amazon.co.uk/gp/product/B07TV9RWLM/ref=ppx_yo_dt_b_asin_title_o03_s00?ie=UTF8&psc=1

The design is on TinkerCad here: https://www.tinkercad.com/things/fo4qDj1Qrwn

Thanks.