The Hends BL254 is a strong, barbless steel hook designed for fly fishing for large fish. Its construction is comparable to that of the medium-strength BL354: in the Hends size chart for sizes #10 through #16, the BL254 has a larger wire diameter for each size.
As a reference, Hends lists 0.69 mm for #10 and 0.63 mm for #12. Sizes range from #6 to #16, in a Black Nickel finish, and are sold in packs of 25.