Amazon.com Digital Gift Cards valued at $100 will be emailed once installation contracts have been paid in full. Amazon Gift Cards valued at $50 will be emailed once annual service packages have been paid in full. Offer is only valid for friends that have not used Professional Irrigation Systems in the last 24 months. Referral program must be mentioned at time of call or 1st contact. Offers not valid on referrals before 1/1/17 . Professional Irrigation Systems reserves the right to change the referral program at any time without notice.