niceeshop(TM) 10Pcs Packaged - Silver BNC Female to Female Coupler Adapters Converter Connector BNC Female to BNC Female connector; Size:3.2x0.9cm/approx 1.3x0.4inches Precision machined,for maximum signal transfer and corrosion resistance Great for connection two BNC cables together It can join two BNC male/male cables together to make a longer cable