In Norse mythology, Járngreipr (iron grippers) or Járnglófar (iron gauntlets) referred to the famous iron gloves of Thor which helped him to grip his hammer, the mighty Mjolnir. Together with the hammer and the belt Megingjörð, Járngreipr was one of the three most important possessions that Thor owned, and further enhanced the god’s strength and power.
The exact origins of Járngreipr are unknown, but it’s known that Thor wore these when he had to use his hammer which had an unusually short handle. So, it’s probable that they came into existence solely to assist Thor in this task.
The reason Thor’s hammer had a short handle was because of Loki, god of mischief, who tried to hinder the dwarf Brokkr when he was forging the hammer. As the myth goes, Loki transformed himself into a gadfly and bit the dwarf, which caused him to make an error, resulting in the short handle.
The hammer was extremely powerful and possibly heavy, yet handling it required exceptional strength, a fact exacerbated by the shortened handle. For this reason, Thor may have had Járngreipr created to help him life and use the hammer.
Depictions of Thor showing him wielding his hammer typically portray him as also wearing the iron gloves.
As the Prose Edda states, Thor’s three most prized possessions were his iron gloves, belt of strength and his hammer.