These items are very poorly made, little more than very cheap shoelaces stitched to the lanyard with a very cheap plastic 'Polaroid' branded cap that slots over the end to disguise the shoddy workmanship.
I felt really cheated when I took these out of the - very hard to get into, totally not frustration free - packaging. Then I had to hunt for a needle to reattach the plastic caps as two of them had come off.
Okay, so, they will do for children's toys maybe. I don't think I can bring myself to use them myself. That said they do seem to be quite strong, though unlike neoprene there is no flex at all. And there's no sliding strap fastener so you can pull it tight over your wrist. The neck straps are jokes really and it's questionable if they're suitable for adults, they are so short.
Wrist strap measures 21cm (with 4cm lanyard)
Neck strap measures 42cm (3.5cm of which is lanyard)
Right, I can get the neck strap over my big head easily enough. I don't think I'd want a camera dangling off it with such a tight strap though.
As mentioned by another reviewer, you're going to want to superglue the caps on as they have a habit of coming off when you handle them. I'd give them 2 stars as they can do the job for some but really, they are so cheap, I am going to stick with giving them one star only in the hope people will better appreciated the quality of these items in regards to their price, which at £5.99 is a nasty joke. If these were sold for a pound you'd expect change.