In order to save packaging space, the handle of the vacuum and the main unit are not pre-assembled, please assemble the vacuum by attaching the handle to the main unit before using the vacuum for the first time. You can also detach the handle from the main unit if you want to store the vacuum in the future. Please refer to the following steps to assemble your WetVac:

Insert the handle into the host and make sure you hear a "clicking" sound to verify the handle is installed successfully.

How to check if it is installed properly: You will hear a clicking sound after the handle is attached to the main unit, please grab the handle and lift the main unit up to verify the handle does not detach from the vacuum.

The following video is for your reference: How to Install and Remove the Handle Bar