TierraCast® 6.35mm bright brass micro washers. 2.4mm hole. Made in the USA from stamped brass! TierraCast provides affordable, quality components that complement a wide range of jewelry designs. Use these washers with TierraCast's 4mm rivets and all 3 sizes of eyelets to embellish, reinforce or adjust thickness of your leather designs or other cold connections. TierraCast Safety Compliance Info.