Object locator sight
Object measuring apparatus
Object measuring system
Obstetric calibration guide
Obturator
Ocean bottom seismic cable connector
Odd offset fabrication kit
Offset adapter connector
Offset electrical outlet
Offset gaging device incorporating a depth measure for bores or
Offset indicator extension
Offset press attachment
Offset sight
Offset tape measure
Offset, extendable, quick-release plumbness indicating apparatus
Oil dipstick guide
Oil dipstick wiper
Oil filling structure of internal combustion engine
Oil filter size determination kit
Oil level gauge