Ade Advanced Optics wjf1327 Hunter's 13.5-27-Inch Heavy Duty Long Bipod + Free Picatinny Rail Adaptor Quality manufactured with cold forged hardened steel and 7075 T7 alloys; These bipods are the heavy duty version with thicker stronger reinforced legs, Heavy Gauge Steel Full Cradle, Heavy Duty Springs; It can handle the heaviest magnum recoil The spring legs can be adjusted and you can pulling the leg from 13.5" to 27" Hinged bases have tension adjustment to eliminate tremor; Bipods have an all-weather black heavy duty anodized finish Attaches to sling swivel stud and comes with WEAVER/PICITINNY RAIL ADAPTER Light Weigh 16.1-Ounces