Disclosed is an apparatus and method for aiding in compressing an extracranial blood vessel, the apparatus having a biasing member, or spring, for producing a constant force, and two elongated curved arms connected to the biasing member for transmitting the force. A processor includes lumen-identification functionality configured to automatically identify one or more lumens in the image. The heat sink defines a plurality of second holes, while the printed circuit board defines a plurality of third holes, and the backboard defines a plurality of fourth holes. The provided interleaving function is suitable for transmitter architectures with multiple encoders. The passage transports the second synthetic resin to nozzle grooves formed in the die, thereby coating the second synthetic resin on a surface of the product extruded from the die having a first synthetic resin.