Conventional pass through the head number of the head 1-4, via a conventional head size 1/2 and 3/4 two kinds. Is circular in shape, the outer diameter of the conventional 85MM, diameter of 55MM. If you need unconventional, please explain in advance specifications. Stainless steel explosion-proof junction box is a wire connector or wire used to protect the turning area with no contact with the outside world to reach an explosion-proof electrical materials commonly used functions. AH-SS stainless steel explosion-proof junction box enclosure using high-tensile stainless steel molding, durable and anti-corrosive.