The Oakheart Armory shields are built to SCA spec so you could take them into the field. I had them make mine w/out the black hose around the edges...it helps to keep it from splintering but is also quite ugly and since I had no designs for fighting in my Templar rig, I opted for it not to be included.
Lord Sagon, from that Defenders of the Cross site that Wolf linked is the man behind Oakheart Armory, him and his brother.
