It ensures water resistant by force of EPDM washer.
It has a great holding strength.
Save time, labor force and cost.
Use minimum 1500 maximum 2500 rotainal speed electricaldrill.
When screwing use nut setter socket.

4,8 X 19MM   

4,8 X 25MM  

4,8 X 32MM  

5,5 X 25MM

5,5 X 32MM

5,5 X 38MM 

5,5 X 50MM