The Gauntlets were created in a new timeline made by Barry Allen and Eobard Thawne, Cisco decided to make a suit for himself, presumably so he could join Barry for whenever he needed help and to help him control his powers.
The Gauntlets help him control his vibrational blasts as he could not properly control them before and could only do it once. He also uses them to help with his interdimensional travel.
In a possible future set in the year 2024 it was revealed that the Gauntlets were destroyed along with Cisco's hands after being frozen by Caitlin Snow as Killer Frost. But this future was erased after Savitar stopped her.