10pcs) EZ-FLUID Plumbing 1/2" C X C LF Copper Slip Coupling Pressure Copper Fitting Without Stop,Sweat Solder Connection for Residential,Commercial - Amazon.com
3/4" Copper Press-Fit Slip Coupling (No Stop) - PEXhouse.com
End Feed 15mm Copper Slip Couplings - Packs of 25 : Amazon.co.uk: DIY & Tools