The classic Chelsea Brogue Boot utilizes a Burnished Servo Lux leather and is on a narrow, more refined last. The style is leather lined on an air-cushioned sole, with a crisp leather welt. Chelsea Brogue Boot. Burnished Servo Lux leather- a smooth leather which is designed to soften over time, treated to create an antique look. Heel loop. Elastic gusset. This is a leather-welted product. The upper and sole are sewn together, not merely glued, like many footwear constructions, and are also heat-sealed. Dr. Martens air-cushioned sole.