Most all common wire nuts are plastic nowadays except for high heat applications. I think these 8 are neat and there are many patents over the years covering them. From Left to Right: WI 4/14 18 yellow, Ideal/8 14 78-13 Grey, Ideal/ 8 22 341 white, Ideal 76 Pat No. 1700985 Brown, Buchannan 10 18 22 Red, Ideal 10 18 96 Brown, GB 8 18 88 Grey, Marr No.R 16-14 Black.