Constructor's gloves are obtained from Temple Trekking by helping Pazuzu to reach level 85. The gloves are a part of constructor's outfit and give 1% boost to Construction experience, while the full set gives a 6% boost.
This reward is claimed through the Noticeboard interface, by clicking on Pazuzu's posting, and then clicking the "Item Reward" button under "Unlocks".
Alternatively, the gloves can be obtained from Vic the trader in Burthorpe as of June 2017.
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