Product review (4 stars): The product "LOOKS" good. The insulation gives the impression of a heavy ...
The product "LOOKS" good. The insulation gives the impression of a heavy gauge wire ,may be 8 or 10. The seller has neither given the gauge nor the material (Cu or Al) of the wire. The difference between 8 and 10 gauge wires is very small 0.676mm  (3.264- 2.588). Only experienced electricians can make out the difference.
Else the product is good. The strain relief clamp was pretty easy to instal. A little dexterity was involved. One must first drive in a mm or two, both the self tapping screws provided into the clamps, then unscrew them out  so that when you do actual fitting the threads are clean and a little wide and  will be easier to start driving the screw in. I installed this clamp after making the connections. Insert both the clamps ears first in to the enclosure. Such that the screw will be inserted from the top. Then drive in one screw a mm or 2 only to hold in place. Now drive in the second just a bit. Just the push /wiggle the cable  through it so that the bared wires are out of the clamp, and tighten the clamp as required .