welding gun, Gas cooled (QQ), water cooled (QS) and WP series are available with more than 60 specifications. ... models availbale for your wide choice: QS-150A, QS-160A,QS-200A, QS-250A, QS-300A, QS-350A, QS-400A, QS-500A, QS-600A, QQ-100A, QQ-150A, QQ ...