Content:1PCS 1/4 BSPT Male Thread Quick Coupler Plug1PCS 1/4 BSPT Male Thread Connector Socket1PCS 1/4 BSPT Female Thread Quick Coupler Plug1PCS 1/4 BSPT Female Thread Connector Socket1PCS 1/4 Barb Quick Coupler Plug1PCS 1/4 Barb Connector Socket1PCS 5mmx8mm Swagelok Quick Coupler Plug1PCS 5mmx8mm Swagelok Connector SocketBSP (British Standard Pipe) Thread Size InformationBSP (British Standard Pipe) size turned into originally in line with the interior diameter measured in inches of a steeltube for which the male thread become intended.This usally reasons confusion ,as humans think the BSP size refers to the outside diameter of the male thread .Example:so if i would like to slot a thread measuring 1” you'll order 3/4” BSP -- see the chart belowBSPOut facet DiamterNormal SizeInchmm1/8DN60.38”9.71/4DN80.51”13.23/8DN100.65”16.71/2DN150.82”213/4DN201.04”26.51DN251.31”33.21-1/4DN321.65”41.91-1/2DN401.88”47.82DN502.35”59.62-1/2DN652.96”75.23DN803.46”87.94DN1004.45”113