Kirby nozzle lock screw.
Kirby part 1211S and 1211.
Examples of Kirby vacuums that use the nozzle lock screw includes:
Avalir, Sentria 2 and Sentria
G10D, G10, G7D, G7
Ultimate G and Diamond Edition
G 2001 Limited Edition (G2001)
G 2000 Limited Edition (G2000)
G six, G6, G5 and G4
Generation 3
Heritage, Heritage 2
Legend, Legend 2
Tradition (3CB)
Classic (1CR), Classic Omega (1CB) and Classic III (2CB)
Dual Sanitronic 50 and 80
Sanitronic VII (516)