Smoke Treating Patents (Class 131/200)
- Filter and/or absorber (Class 131/202)
- Spiral passage (Class 131/209)
- Serial checks or baffles (Class 131/210)
- Chamber enclosed tubes or nipples (Class 131/211)
- Plural reversely extending passages (Class 131/213)
- Bowl detachable from neck cup (Class 131/214)
- With valve in smoke path or removable, external passage closure (Class 131/215.1)