QQQ brand octal sockets from Japan. Similar in size, construction and quality to the old British McMurdo sockets we used to sell. Black phenolic body, tinned wraparound cup contacts, single hole in solder lugs, 'molded in' nickel plated metal mounting ring. Can be installed "Sub-panel"/bottom mount or top mounted. Bottom of phenolic body is gently tapered; why don't other tube socket manufacturers do this; it's a great idea. Fits approx. 1.1875" hole for top or bottom mounting, 1.5" (1&1/2") mounting centers.