The Bostitch 10.320.5152 Standard Male Hose Connector from Bostitch.
A standardmale hose connector for use with Stanley Bostitch range of Compressors.
CEJN 320 series.
1/4in B.S.P. fitting
Loads more than in a shop, and without needing to navigate all the aisles
Whichever suits you best
Like Macgyver but online