Pennsylvania Statutes Title 43 P.S. Labor § 1101.904. Existing agreements; provisions inconsistent with act

Any provision of any collective bargaining agreement in existence on January 1, 1970 which is inconsistent with any provision of this act but not otherwise illegal shall continue valid until the expiration of such contract. The parties to such agreements may continue voluntarily to bargain on any such items after the expiration date of any such agreement and for so long as these items remain in any future agreement.