http://artofstrength.mybigcommerce.com/products/kettlebell-buddy.htmlThis week's Minute of Strength Anthony walks you thru progressing with a Kettlebell Buddy. A look into how important the buddy can be for safer progressing.DescriptionThe Kettlebell Buddy adds progressive weight to your when the jump from one kettlebell to the next is too much. Screw the Buddy to the base of your Punch Kettlebell and move past your sticking points, progressing to the next size bell faster and safer than before. Quality Note: Made in the U.S.A. Specs:Weight: 2kg and 4 kg options