If the goods are defective on delivery or become defective within twelve months after receipt by the customer, and such defects arise in either case from faulty workmanship or materials in manufacture, Pneumatrol will at its own expense replace or repair the defective goods at Pneumatrol’s discretion unless the defects arise either from materials or workmanship specified or supplied by the customer or from the Company manufacturing the goods to the customer’s satisfaction. Warrantee obligations are limited to those liabilities stated above irrespective of the cause.