Unlike the Commons, the Lords uses two maces, one dating from the time of Charles II and another from the reign of William III.
They are symbols of royal authority, and without the mace in position the House cannot sit, debate or pass legislation.
One of the maces accompanies the Lord Speaker. It is carried into the Chamber in the Lord Speaker's procession and is placed on the Woolsack whenever the House meets.
The other is carried with the Lord Chancellor when he is performing official duties outside the Chamber.
The mace is absent during the State Opening when the Sovereign is in the chamber in person.