8x21 Jupiter III Clam Pack...Weighting only 6 ounces, these feather-light binoculars are ideal for casual use. Yet despite their diminutive size, the PENTAX Jupiter III series still com standard with premium PENTAX features. High-quality BaK4 prisms and SMC optics for sperior image quality and minimal glare. Rubber eyepiece rings for viewing comfort. And a compact, ergonomic body design that fits neatly into a pocket or purse. Wehther attending a sporting event, traveling, or hiking, the PENTAX Jupiter III binoculards provide great optics at an affordable price.