Original US TABER S-34 zinc plates, S-34 standard zinc plate S-34 standard zinc plate NEMA standards board, 0.032 ", zinc, 1/4" hole, 5. S-34 Zinc Standardization Plates are used to evaluate the abrasion characteristics of S-42 and S-33 sandpaper strips. Each plate is 4 "square, .032" zinc with? "Center hole. (5 pcs.) Simai professional equipment sales instrumentation, standards, testing supplies and spare parts, sales hotline: 13712926405 Mr. Zhou.