Spiked Leather Armor

A variation of studded leather that is sometimes seen among barbarians of northern climes (and, oddly, among some hill giant clans) is spiked leather. Much as it sounds, spiked leather armor is studded leather armor in which the rivets have been augmented by sharp spikes. (Most intelligent beings would be worried about mounting spikes into their armor, just in case they should trip and fall, not to mention the problems packing or storing the armor).
Overbearing and grappling while wearing such armor inflicts additional damage based on the wearer's size. A small creature inflicts 1-2 points of piercing damage, a man-sized creature inflicts 1-3 points, and a large creature inflicts 1-4 points. These values are considered for each individual attack, not for every round that a creature is grappled.
Spiked armor is usually made specially for the wearer and costs about 150% of the price of a normal set of studded leather.
Spiked armor is occasionally used to equip gladiators, pit fighters, and other specialists.