Our fire sprinkler covers can prevent foreign matter from entering the hydrant and protect the female threads on the fire department inlet connection (FDC). These fire department connection caps are made of forged aluminum; The outdoor sprinkler cover is rust and corrosion resistant so you can use it exposed to the sun and rain. You will receive a total of 2 fire sprinkler head covers, the color is red, each with 2 pieces of eyebolts with nuts, you can use it to connect the female pin lug swivel joint. Unlike ordinary plastic shower caps, ours is made of aluminum, which can withstand high and low temperatures without deforming, so you can use it with confidence. These caps will fit the most common fire department connection (FDC) 2 1/2" NH / NST. Caps are designed to cover any FDC with the outside diameter (Not including pin lugs) of 3 7/8".