Providing Make-Up Air For Exhaust Devices Is Easy, Controlling It Is Not - Until Now. Best® Linklogic® Make-Up Air Dampers, When Interlocked With Slave Dampers, Open In Unison To Provide Synchronized Operation For Kitchen, Bath And Whole House Ventilation Products. For Use With Smartsense® Ventilation Fans And Select Best® Range Hoods To Provide Balanced Indoor Air Pressure. Linklogic® Installs In Any Electrical Box For Simple Installation. The Intelligent Design Options Ensure Optimum Performance In A Variety Of Installations And Applications.