Arlington Floor Box Kits Arlington’s UL Listed FLOOR BOX KITS offer installers the low cost, convenient way to put a receptacle in the floor – with a box that installs flush with the floor. We have a floor box for nearly any job site condition. There's one for new concrete pours, a box for existing floors – and an adjustable box that fits most finished floor heights up to 2". All are available with oversized non-metallic or metal covers. And all install flush with the floor surface.