| Inbound Relationships | Type | Active | Source | Characteristic | Refinability | Group | 
| Helium/oxygen quick-connect coupling, male | Is a | True | Pneumatic quick-connect coupling | Inferred relationship | Existential restriction modifier |  | 
| Surgical air quick-connect coupling, male | Is a | True | Pneumatic quick-connect coupling | Inferred relationship | Existential restriction modifier |  | 
| Nitrous oxide quick-connect coupling, male | Is a | True | Pneumatic quick-connect coupling | Inferred relationship | Existential restriction modifier |  | 
| Nitrous oxide quick-connect coupling, female | Is a | True | Pneumatic quick-connect coupling | Inferred relationship | Existential restriction modifier |  | 
| Medical air quick-connect coupling, female | Is a | True | Pneumatic quick-connect coupling | Inferred relationship | Existential restriction modifier |  | 
| Helium/oxygen quick-connect coupling, female | Is a | True | Pneumatic quick-connect coupling | Inferred relationship | Existential restriction modifier |  | 
| Anesthetic gas scavenging quick-connect coupling, male | Is a | True | Pneumatic quick-connect coupling | Inferred relationship | Existential restriction modifier |  | 
| Nitrous oxide/oxygen quick-connect coupling, male | Is a | True | Pneumatic quick-connect coupling | Inferred relationship | Existential restriction modifier |  | 
| Medical air quick-connect coupling, male | Is a | True | Pneumatic quick-connect coupling | Inferred relationship | Existential restriction modifier |  | 
| Nitrous oxide/oxygen quick-connect coupling, female | Is a | True | Pneumatic quick-connect coupling | Inferred relationship | Existential restriction modifier |  | 
| Vacuum quick-connect coupling, female | Is a | True | Pneumatic quick-connect coupling | Inferred relationship | Existential restriction modifier |  | 
| Anesthetic gas scavenging quick-connect coupling, female | Is a | True | Pneumatic quick-connect coupling | Inferred relationship | Existential restriction modifier |  | 
| Oxygen quick-connect coupling, female | Is a | True | Pneumatic quick-connect coupling | Inferred relationship | Existential restriction modifier |  | 
| Oxygen quick-connect coupling, male | Is a | True | Pneumatic quick-connect coupling | Inferred relationship | Existential restriction modifier |  | 
| Surgical air quick-connect coupling, female | Is a | True | Pneumatic quick-connect coupling | Inferred relationship | Existential restriction modifier |  | 
| Vacuum quick-connect coupling, male | Is a | True | Pneumatic quick-connect coupling | Inferred relationship | Existential restriction modifier |  |