Check the listing for details. Countersunk Plug Hex Head Socket M16 x1.5 Male Stainless Steel Pipe Fitting 2Pcs. Condition: New. Listed at 17.46 USD. Features:1. ✔ 304 Stainless Steel for corrosion resistance, ductility at high temperatures, and low magnetic permeability2. ✔ It is a silver tone outer Hex Head Pipe Connector that is for closing and terminating the end of a pipe.3. ✔ Great for blocking off intake manifold water ports, water pump ports, water temp and oil sender holes, engine block .4. ✔ In order to enhance the sealing performance,you can use O rubber ring.Specifications:Thread: M16*1.5Thread length:8mm/0.31inchHex Width :8mm/0.31inchMaterial: 304 Stainless SteelTotally Size:16mm x 21mm/0.63inch x 0.83inch(L x Max.D) Package includes: 2pcs x Hex Head Plug Description:Pipe fittings are components used for connecting, terminating, controlling flow, and changing the direction of piping in many different industries.