Door latch, also called door lock mechanism, were produced by industrial steel plate. There are three standard sizes of HY ENVIROTECH’s door latches, generally used for 10-40 yard roll off containers. 31" door latch system is made up by a door handle, a moving bar, a mounting bar, a bottom latch and one latch. Different sizes of roll off container determine different number of latches. This type are usually used for 10 yard roll-off containers.