A brazing system has a first gas source, a second gas source, an enclosure, a brazing torch, and a control system configured to control a ratio of the first gas source and the second gas source.

A combustion tool with a detachable heating unit includes: a main body having an insertion pipe, an outer circumferential surface of the insertion pipe is axially formed with at least one insertion having a wedge locking tenon disposed therein; and an unlocking mechanism including a push button, the push button has a block sheet abutting against an elastic member, the block sheet compresses the elastic member, and the push button is automatically recovered to an original position through the elastic member; and a heating unit including a fasten ring and a heating pipe, an elastic support arm is axially protruded from the fasten ring, one free end of the elastic support arm is disposed with a locking hook inserted in the at least one insertion slot and moved along a the wedge locking tenon to form a locking or an unlocking status.

A tool with a supporting function includes a main body and a support; an accommodation space having a front seat and a rear seat disposed at two ends thereof and allowing the support to be accommodated is formed on the main body, a push bottom is sheathed with the rear seat to be operated to slide on the rear seat between a first position and a second position, a locking mechanism for locking or unlocking the support is disposed between the support and one end of the support, a pivotal connection mechanism is disposed between a pair of support arms at another end of the support and the front seat, the support can be outwardly rotated from the accommodation space with the pivotal connection mechanism served as a pivot for supporting the tool, or inwardly rotated to be placed in the accommodation space.