Black wire commercial grade outdoor light strings available with e12, e17 and e26 bases. The black wire intermediate base (e17) outdoor stringers will use a C9, G50 or S11 bulbs and the black cord medium base (e26) stringers use the s14 bulbs that are available in both LED and incandescent. The e12 light strings will use g30, g40 or C7 LED or incancescent bulbs.