Stinger Spike System spikes are hollow. This allows air to escape at a controlled rate without causing a blowout or sudden loss of control. The spikes are 2.1" in length and are made of 304-T7 stainless steel. The XL's 2.1" length spike acts in conjunction with our patented rock-and-tilt mechanism base. This Stinger technology effectively penetrates thicker tires to safely and quickly end pursuits involving many larger vehicles including large trucks, farm vehicles, and military-type vehicles. Hollow spikes allow air to escape at a controlled rate Employs a new longer spike length for thicker tires Extends to 15.5-feet for multi-lane use The Stinger XL is a 15.5-ft wide system that covers multiple traffic lanes and is furnished with replacement spikes, safety tip guards, and a spike replacement tool in a compact, quick-deployment carrying case. Additional Stinger replacement spikes are provided free of charge. Includes 40ft Rope w/ Handle Spike Replacement Kit Spike Insertion Tool Hard Storage Case Specifications Model Extended Length (ft) Spike Length (in) Spike Count Dimensions (HxLxD) Shipping Weight (lbs) Metro 10' 1.8" 70 18"x20"x3.5" 11lbs Trooper 15.5' 110 18"x20"x3.5" 15lbs Defender 25' 180 21"x24.5"x3.5" 14.5lbs Stinger XL 15.5' 2.1" 110 18"x20"x3.3" 15lbs