: Found in the Idrobase - EnviroSpec Full Line Catalog , this refers to specific O-rings used in seal kits for professional pump systems like Kärcher or Interpump.
If you are looking for a camera dolly guide, "22" often refers to the track width or a specific model version. Dolly 22 (1980s) PDF
: While "Dolly 22" isn't a standard model name like the Chapman or Fisher dollies, 1980s filmmaking relied heavily on wheeled carts for smooth horizontal movements. : Found in the Idrobase - EnviroSpec Full
: For military or heavy-duty vintage dollies, the Dolly Set Maintenance Manual provides detailed PDF instructions on air reservoir draincocks, brake shoe handling (warning of asbestos in older models), and hub rotation. : For military or heavy-duty vintage dollies, the
: These parts are often part of a larger "Dolly Kit" (such as Kit 22) used for maintaining pump head rings or plunger seals. 2. Heavy Transport & Trailer Equipment