Master Homecraft Co. received a promissory note with a stated face value from Sally and Tom Zimmerman. The note was payment for remodeling their home and contained unused blanks for installment payments but contained no maturity date. When Master Homecraft sued the Zimmermans on the note, the couple argued that they should not be liable on the note because it is impossible to determine from its face the amount due or the date of maturity. Decide. [Master Homecraft Co. v. Zimmerman, 22 A.2d 440 (Pa.)