they are called steel balls. Granted, they are found inside bearings, hence the name ball bearing. It is not a ball bearing in the end of a pen, it is a steel ball
vulpecula999 1 year ago
first 'controlled' powered flight, but the error is forgivable...
felderup 1 year ago
they are called steel balls. Granted, they are found inside bearings, hence the name ball bearing. It is not a ball bearing in the end of a pen, it is a steel ball
vulpecula999 1 year ago
first 'controlled' powered flight, but the error is forgivable...
felderup 1 year ago