Bachelor buttons (or tack buttons or dungaree buttons) are best described as the button used on Levi-brand jeans.
It attaches with a sharp prong and is used in conjunction with a buttonhole.
Tack buttons bachelor buttons and dungaree buttons are interchangeable.
Pre Packaged in sets of 4 (Bronze) or 6 (Antique Gold and Silver)
Insert prong (nail) into jeans/pants (from the wrong side). An awl may be beneficial to make an opening for the prong.
Apply button over prong, push to keep together.
Place the jeans with button (side down) on FIRM surface.
Protect button face with a bit of cloth.
A block of wood on a sturdy table to protect the surface.
Hammer firmly, (from the prong side) to attach button.