Both the Hyperbell bar and kettlebell attachment are exactly what I've been looking for. I have a full set of dumbbells, but sometimes the workout that I'm following has moves using a bar or a kettlebell. While I can usually modify the move to use dumbbells, it often makes things more difficult, or takes more grip strength and I wear down too fast. Both of these products are very well made and lets me perform these moves without needing to buy a lot of extra equipment. They fit perfectly on my rubber coated hex dumbbells (which also have the rubber coating on the handles).