It works perfect with brass nozzle and barrels.
It specialized for Makerbot structure of 3D printers.
Aluminium with anodized surface.
Accept Nozzle with M6 threads.
Inner hole for heater tube: 6mm
Inner hole for thermocouple/thermistor: 3mm
Inner hole for set screw: M3
Package: Quantity: 5 pcs Heater Aluminium Block