The DFS-2000 and Q-2500 are North American Signal Co.'s most powerful strobe lights with candela/second ratings of 1500 and 2500 respectively. These lights are excellent for advance warning and for increased visibility in bad weather. They feature a black powder painted aluminum base (or an anodized aluminum base signified with "SP" in the part number) with a tall fresnel lens and CLEAR outer dust cover. High profile and high performance. Replace the last "X" in the part # to designate the lens color: A-amber, R-red, B-blue, C-clear, G-green