About this item Well Made: Heavy duty extruded aluminum construction, professional sandblast/matte anodized finish. Built-in slots/grooves are for holding PCB or circuit boards. The sliding cover design allows the top part of the extrusion to slide smoothly, making it easy to access inside to mount parts or components. Color: Black External dimension: 1.81'D x 2.99'W x 4.33'H Interior dimension: 1.81'D x 2.52'W x 1.69'H. Application: Electronic projects like switch/converter, power supply units, audio amplifier projects, ham radio projects, etc. Dimensions: 1.81'D x 2.99'W x 4.33'H.