For sale is a Siemon Co. Type B3-50MH-49, 300 Pin Terminal Block with Metal Enclosure. Typically used in telecommunications installations. This item consists of (1) S66B3X50 terminal block, and (1) MH-25 gray metal housing. 17-1/8" (H) X 5-1/4" (W) X 2-1/8" (D) Overall size of enclosure.