A mechanical thrombectomy device system is disclosed that is made from a single piece of biocompatible material, including a proximal flow block portion/feature, and/or, a flow block feature in the device body portion, a guidewire like delivery portion and an expandable, treatment portion. The construction of the device from a single piece allows for a seamless transition from the delivery portion to the treatment portion, thus removing any joints or bonding of the two portions together as separate pieces. This improves the strength of the system as a whole and greatly reduces the possibility of the two parts unintentionally detaching from each other. Likewise, the distal treatment portion is cut from a piece of material the same size as the proximal delivery portion, allowing the device to be compacted to a similar size profile giving it delivery advantages including a lower delivery force required and requiring small access systems, and the treatment portions surface can be altered to enhance embolus affinity by either coating with a substance or changing the texture by mechanical or chemical means.