Commercial O-rings made from 13 different rubber compounds were tested for physical properties after 7 and 12 years of shelf aging. No gross changes were observed in tensile strength, elongation, or compression deflection characteristics. Wood, T. E. and Stone, W. P. Marshall Space Flight Center NASA-TM-78150
ThriftBooks sells millions of used books at the lowest everyday prices. We personally assess every book's quality and offer rare, out-of-print treasures. We deliver the joy of reading in recyclable packaging with free standard shipping on US orders over $15. ThriftBooks.com. Read more. Spend less.