Parco Inc handles design, sales & service needs. We are a Federal APD Authorized Distributor. Don Clark-President. Federal APD is the largest U.S. manufacturer of parking, access and revenue control systems. At Federal APD, where the first completely integrated facility management system software was introduced to the parking industry, insights translate today's answers into tomorrow's successes. HySecurity gate operators meet the most stringent governmental, industrial, corporate and residential security and reliability requirements.