SMC VP517KY-5YO1 Residual Pressure Relief Valve MSRP: Now: $76.60 Was: VP517/717, 3 Port Solenoid, Residual Pressure Relief, Modular ConnectionVP5/717 series is a residual pressure relief 3 port valve with modular connection to SMC s AC series F.R.L unit. It allows for... VP517KY-5YO1