Protect yourself from the elements with a Propper® Boonie. Sewn to military specification MIL-H-44105B, the Boonie hat includes vent holes on either side to allow for air circulation Our eBay Store Propper Boonie – 60/40 Ripstop Protect yourself from the elements with a Propper® Boonie. Sewn to military specification MIL-H-44105B, the Boonie hat includes vent holes on either side to allow for air circulation. Use the adjustable chin strap for a secure fit. 60% cotton / 40% polyester ripstop Sewn to military specification MIL-H-44105B Metal vent holes Adjustable chin strap Imported