This rubber dust blower is used to blow dust and debris from parts, movements, and cases, it is indispensable. This is one of the most constantly used tools on the watchmaker's bench. One way valve draws air from the back and blows it out the front end. Metal nozzle is also used by many watchmakers to remove crystals by blowing a puff of air into the crown sleeve. Also used by photographers to clean camera lenses and parts. Made in China.