Little Hotties 07221 Hand Warmer, Air Activated, Up to 10 hr, 135°F Avg Temp, 2 in Wd, 40 PK 387WF1 Flow coefficient (Cv) is the Flow coefficient (Cv) is the amount of water (in gallons per minute) at 60° F that will flow through a fully open valve with a difference of 1 psi between the inlet and the outlet Waterproof Typical Rubber Boot Application Moderate Chemical Resistant Footwear Style Pull On Footwear Sole Pattern Lug Toe Type Steel Insulated No Color Black Predominant Footwear Color Black Upper Color Black Metatarsal Guard No Style Number 75109 Gender Men's Insulation Type None Footwear Closure Type Pull On Midsole Material PVC Outsole Material PVC Toe Shape Round Upper Material PVC Standards ASTM F2413 18 Resists Chemicals For Outdoor Traction Yes Shank Material Steel Closure Type Pull On Waterproof Yes Electrical Hazard Rated Yes Oil Resisting Sole Yes Static Dissipative No Insole System FootForm(TM) Chain Saw Cut Resistant No Puncture Resistant Insole No Ninety Degree Heel Yes Completely Non Metallic No Removable Insole Yes Wide Toe Cap No Shoe Style Knee Footwear Shank Yes Features Triple Density Technology (TDT) Chemical Resistance Province of China Pockets Reusability Disposable Number of Warmers Included 40 Country of Origin Taiwan