CEE plug - Cheap but secured the front and rear part with a locking lug

This 400 V plug corresponds to the now widely encountered, simple CEE plug.
The front and rear parts are screwed "in itself" and only secured with a small locking lug. In the rear part of the strain relief connector is integrated. This can be achieved by turning fix the white cap. The relief I detected immediately and originally thought that no present (description and assembly drawings are missing). Taken overall, the plug difficult to insert and remove, but this is almost always the size and the general nature of these plug owed. As you drag, however, I have in mind already that both connectors can loosen them, because they are not fixed with screws (only the small latching lug which is intended to prevent untwisting). There are also rubber seals in Kabeleiführung and between front and rear part, but the fact that both parts are not screwed tightly with screws is not the plug in the middle Waterproof.
For home and garden suited as for "professional stresses" no more!