Stoncos 3300 Series Medium base lampholder is ideal for use over entrance ways, under eaves, over signs, any safety, security, temporary or recreational lighting. Areas requiring good color rendition, instant-on, dimming capability, easy installation and low initial cost.Precision die-cast aluminum with heat sinks and ribs to maximize heat dissipation. Premium porcelain socket with reinforced screw shell and center contact. 3300 Series equipped with durable rubber gasket.