I bought 1 pack of them a while ago when I saw it on sale. You poke the weight through the worm and then thread the hook through that slot at the top of the weight. The slot ends up in the middle of the senko.
What I found was that the senko tore up way more using this setup. I have moved on to a weighted wacky hook. The VMC ... 1/16 to 1/8 mainly.