Tumbling media use as burnishing metal for its maximum brightness. It is made of 304 stainless steel which is rust and corrosion proof. Due to its small size it is ideal for jewellery making purpose. It is abrasive resistant as compare to cast media. It contains 4 shape mix media (25% each): Stainless steel balls. Stainless steel Balcones. Stainless steel plain media pin Stainless steel Diagonals (Cross pin) Specification: Material : 304 Stainless steel Dimension of Media : 1/8" Stainless steel balls 1/8" Stainless steel Balcones 0.078" (diameter) x 0.236"(length) Stainless steel plain pin 1/10" x 1/4" Stainless steel Diagonals (Cross pin) Weight: 2lb *Final product has some dimension tolerance but operational function remains the same.