Eliminates damaged mandrels and out-of-round pen blanks by putting pressure directly on the pen bushing, not the mandrel Provides no pressure on the mandrel thus eliminating any bending and vibration Used in tailstocks to secure pen blanks on the mandrel Adapts to almost every mandrel with a shaft diameter of .245 inch (6.22mm) or smaller; mostly commonly used with 7mm mandrels There is no longer a need for spacer bushings, Manufacturer: Fuhjythy