The gauntlets are insulated gloves that allow the user to grasp the Staff of Horus. The glove's magnetic shielding allows it to disable the staff's magnetic polarity. They were designed and created by Cisco Ramon.
The Flash used the gloves against Vandal Savage in order to get the Staff of Horus from his possession. The gauntlets worked perfectly, due to Barry's knowledge of a prior timeline, and this allowed both the Flash and Green Arrow to get ahold of the staff and use it to defeat Savage.