Facom 3/4" Drive Tamper Proof XZN (Triple Square) Impact Socket - M16 (NKVR.16) - heavy duty socket for higher torque applications with VW/Audi/Porsche gearbox and brake applications. I used to sell a cheap 1/2" drive version (non Facom) and had a few failures. You're more likely to break your driver or the fastener you're working on before this socket fails. Height = 50mm. Weight - 217gr.

(Note - this tool has a hole in the tip for "tamper proof" applications but will work fine as an M16 socket even when this feature is not required)