This dragon ball papercraft is Future Trunks and his Time Machine, the paper toy is designed by SuperVegeta71290. The Time Machine is a machine built by Future Bulma, the Bulma of Future Trunks' alternate timeline, that could be used to go to the future or to the past.
When traveling back in time, the time machine creates a new timeline that branches off from its original one at the moment in time where the time machine arrived. Thus it is not possible to "change" the past, in the sense that one's present will change. Any change done in the past will be reflected in a new timeline. However, when traveling back to the future, the time machine will go back to its original timeline, and not to the new timeline's future. If it is used to travel again back to the past to a point after a previous trip, the time machine will go to the newest timeline.
According to Future Trunks, the time machine uses up a lot of energy, so it can carry barely enough power for two trips in time. Thus, it is generally used to travel in time, and then to go back to the present. Recharging the machine takes a lot of time, too. It seems that the only way to recharge it is in Future Trunks' own time.
In a promotional movie for Dragon Ball Heroes, the Saiyan Hero and the Saiyan Heroine use Time Machines to go back in time and attack Frieza's remaining soldiers while Super Saiyan Goku is fighting Frieza on Namek.
You can download this paper craft template here: Dragon Ball Z - Future Trunks In His Time Machine Free Paper Toy Download