This is a quality marine grade stainless steel (AISI 316) chain ideal for marine applications or where corrosion resistance is required. Great for light applications that require corrosion resistance. The link size is 5.5mm (between 3/16" and 1/4") in the imperial equivalent. There is 50' of chain. 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.