This is for fifty (50) quality marine grade stainless steel (AISI 316) pad eyes. The pad eyes are in the US specification of 3/16", the metric equivalent is generally considered to be 5mm. The overall length is 2". AISI 316 stainless is a premium grade of stainless and is considered by many to be best in class. 316 stainless is corrosion resistant and very durable even in the harshest of conditions.