Steel gauntlets

Steel gauntlets are a reward for completing the Family Crest quest. Players can take them to any of the three brothers from the quest and have them enchant the gauntlets with a special ability. The magic of these gauntlets will always return them to the head of the Fitzharmon house should they be lost, so if a player loses the gauntlets, they can be retrieved from Dimintheis with their previous enchantment. Before completion of the Family Pest miniquest, players can only have one effect at a time, and it will cost 25,000 coins to change the effect of the gauntlets. After completing the Family Pest miniquest, however, Dimintheis will hand the player as many pairs of steel gauntlets as they want.

Cooking gauntlets
Bring the family gauntlets to Caleb. You can find him North-east from the Catherby bank. Cooking gauntlets greatly decrease the chance of burning fish, particularly lobsters, swordfish, monkfish and sharks.

Goldsmith gauntlets
Bring the family gauntlets to Avan at the Al Kharid mine. Goldsmith gauntlets increase the Smithing experience of smelting gold from 22.5 to 56.2. This makes smelting gold bars more efficient, and allows players to earn over 300k smithing xp per hour at the Blast furnace, the fastest training method in the game.

Chaos gauntlets
Bring the family gauntlets to Johnathon in the Jolly Boar Inn north-east of Varrock (near the Wilderness border). Chaos gauntlets increase the damage done by bolt spells.