Fangrui Product Details Product Wiring Method: The Yellow And White Wires Are From The Relay, The Yellow Wire Is Connected To The Device, And The White Wire Is Connected To The Switch The Black Wire Is Connected To The Negative Pole Of The Battery; The Red Wire Is Connected To The Positive Pole Of The Battery.this Product Is An Automotive Relay Fuse Box, Using 12v Power Supply, With A High-capacity Bracket, Including Five 40a Jd1914 Relays And One 4 Pin Rtt7121 Relay, And Six Fuses Of 5a, 10a, 15a, 20a, 25a And 30a. The Relay Fuse Box Is Made Of High-quality Nylon Material, With A Flame-retardant Shell, Each Has A Precise Opening, And An Arc-shaped Socket Is Reserved On The Make All The Wiring Neat And Beautiful. All The Necessary Wires Of This Car Relay Fuse Box Are Pre-wired And Can Be Connected To The Car, Avoiding The Trouble Of Wiring. It Is More Convenient To Install And Use. This Relay Fuse Box Has A Powerful Insulating Shell With Waterproof And Dustproof Top And Bottom Covers, And The Wire Opening Hole Is The Outlet Of