Posted By: bandit
As you can see, this new strap includes a little locking clip, replacing the sliding clip of the previous models, which had a tendency to slide away from the player's wrist and loosen the strap. This new model would be the fourth incarnation of the strap; the first was the original model which tended to break, the second would be the replacement straps with the thicker connector to the remote, and the third was the replacement of the replacement that lacked the Nintendo and Wii branding.
These were said to be obtained by requesting replacement straps. No official announcement has been released regarding these straps. If you have already requested four (4) straps from Nintendo, when they first announced the replacement with the thicker string, you'll have problems. Nintendo requires you to enter your Nintendo Wii serial number when requesting the straps and when you request up to four straps, it will give you a message... "Your request for additional strap(s) has exceeded the maximum quantity allowed per Wii serial number." So if Nintendo really is shipping these new locking wrist straps, you'll have to enter a new Nintendo Wii serial number.
If we hear anything more concrete and official, we'll update this post.
Source: NintendoWorldReport