Shop for Free Weights from Hayneedle.com! Get precision workout with the Troy Barbell Add-On Weight. While most weight stacks are in ten-pound increments, this add-on is available in a 2.5- or five-pound option for a workout in smaller increments. The weight fits on top of the head plates on a weight stack machine, and it's made of iron with a rubber casing.About Troy Barbell:Since 1987, Troy Barbell has been developing and manufacturing free weights and fitness equipment while providing unparalleled quality, service, and satisfaction to its growing customer base. Today, the Houston-based company is one of the top free-weight manufacturers in the industry with a diverse range of products and a full commitment to use only the highest grade materials and designs. The Troy family consists of three lines: USA, leading-quality home fitness; VTX, committed to specialty and training applications; and Troy, the premium line of free-weight equipment for commercial and institutional use.