I have one of the originals, always carry it with me on my kayak. Not only can you use it to grab onto a limb, you can also grab a handful of grass or reeds, or the stem of a lily pad (or a folded pad leaf) and use those as anchors.
If you can't find one, Adrian Acosta at Mariner Sails posted (on Facebook) and showed a photo of one they are now carrying at Mariner Sails in Dallas. It is a new version of the old original. Call him first if you plan on going over to make certain they have received the brush clip anchors.
They really help anchor a vessel in many conditions where an anchor isn't feasible.