All new televisions sold in this state after January 1, 1995, shall be equipped with a time/channel lock or shall be sold with an offer to the customer to purchase a channel blocking device, or other device that enables a person to regulate a child's access to unwanted television programming. All cable television companies shall make available to all customers at the company's cost the opportunity to purchase a channel blocking device, or other device that enables a person to regulate a child's access to unwanted television programming. The commercial television sellers and cable television companies shall offer time/channel locks to their customers, when these devices are available. Notice of this availability shall be clearly made to all existing customers and to all new customers at the time of their signing up for service.