The 523 is a 3XL version of the 516. To compensate for the additional leverage generated from the extended length I increased the wire diameter by one size, e.g. 523 #10 and 516 #8 have the same wire diameter.

As with all Firehole Sticks, this hook is made from high strength carbon steel, which is properly hardened and tempered. The hook is chemically sharpened and finished with a black nickel coating.