IPI accepts cash, checks, money orders, wire transfers, and/or Visa, MasterCard, American Express, and Discover payment methods. For registered customers that have established credit with IPI, payment terms are net 30 days from the date of invoice. Other credit terms or conditions may apply as required for approval by the IPI Credit Department. Anticipation and cash discounts are not allowed. IPI shall have the right of set-off and deduction for any sums owed. If a customer fails to make payment within thirty (30) days, IPI may defer shipments until such payment is made, or may at its option, cancel all or any part of the unshipped order. Customer agrees to pay interest on all past-due sums at the highest rate allowed by law.