A device for applying compression treatment to a part of a wearer's body includes at least one inflatable bladder formed from opposed layers of bladder material. The bladder is constructed so that when worn on the part of the wearer's body inflation of the bladder applies a compressive force to the part of the wearer's body to move blood within the wearer's body part. The at least one bladder has a generally S shape compression region with first, second and third spaced apart sections in fluid communication. At least one opening is formed between the first and second sections. The at least one opening extends through both layers of bladder material to provide communication from an area under the layers of bladder material to a location above the layers of bladder material.