Most Persian Tehran rugs were mid-sized rugs, and they were woven with asymmetrical knots in a variety of grades ranging in knot density from the low one-hundreds to over eight hundred. The Tehran production may claim at least one famous master weaver, Seyd Abolfat-Rasam Arabzadeh. From the outset Tehran rugs established a reputation for good quality, but in the last sixty years their quality has actually improved under the direction of new master weavers, causing them to be more and more sough after.