Niche denim is synonymous with rarely used old-school manufacturing methods, clever (or cleverly simple) small-batch fabrics, and a general quest to trick out the most classic of garments in ways that would be imperceivable without a triple-take or closer inspection.

Iron Heart continues in this tradition with their 21oz. IH-555SG jeans, available in indigo and black with their super-slim 555 cut, and of course have done the iconic five-pocket design everyone’s accustomed to. The made-in-Japan jeans feature a high-rise, lined pockets, button fly, and belt loops sewn onto the waistband, and in their signature fashion, they offer the heft, and potential for great fades, that goes hand-in-hand with heavyweight denim. But here’s where it gets clever—this isn’t denim. No, this is serge fabric which is a cotton twill similar to denim, but with a slightly different weave. If you’re looking for some subtle differentiation that offers a really nice character upon closer examination, this one’s worth a look.

Available for $400 at Iron Heart.