Salco Products (SP3754CS) 3/8 x 4-Inch (3/8"x4") Carbon Steel Seal Pin Assembly features a carbon steel seal pin that is 3/8-inch thick with 4-inches of usable length, and an overall length of 4-3/4-inches. The toggle (flapper) holds the pin in place, and features an elongated 3/16-inch seal hole. Welded to the end of the pin is 13 links of 3/16-inch, carbon steel, chain with a length of 12-inches.