Mount the undermount installation kit (Model #: ABUMSB) to the inner side walls of your cabinet. We then recommend putting plywood on the rods to create a large smooth flat surface. Drill the necessary drain holes. If you did not purchase the kit you will need to create a custom support using 2×4’s. ALFI brand AB503UM Features: Covered under ALFI brand’s 1 year limited warranty against manufacturing defects and 10 year limited warranty against fading/ staining of the glaze Constructed of solid high-grade fireclay material, ensuring durability and longevity Single basin design provides maximum workspace Undermount installation Rear drain location increases workspace area in the sink as well as storage area underneath ALFI brand AB503UM Specifications: Length: 23-3/8″ (left to right) Width: 16-1/8″ (front to back) Height: 8″ (top to bottom) Basin Dimensions: 21-3/4″ L x 13-3/4″ W x 7″ D Drain Location: Rear Drain Connection Size: 3-1/2″