Keson RF18M200 Fiberglass Tape Measure Refill Blade for OTR18M200, 200-Foot/60-Meter 40,000 Fiberglass strands for greater tensile strength and superior accuracy when tension is applied Two coats of PVC protect the tapes from breaking, and a blade shield adds strength to the attachment Keson fiberglass reinforced tapes are designed to withstand more wear and tear than any other type of fiberglass measuring tape Fiberglass Tape Measure Refill Blade for OTR18M200