13/16" diameter, hole size 4mm, metal button with OM symbol. Shank back.
Bali Star Copper/Black Metal Button, Darker Version 13/16" / 20mm #SWC-148
Re-Stocked, Authentic Indian Head Nickel Shank Button 7/8" USA-Made, #SW-32
Re-Stocked, Authentic Buffalo Nickel Coin Button Shank Back, 7/8" USA #SW-31
Bali Star Copper/Black Metal Button, Lighter Version 13/16" / 20mm #SWC-147
Mystic Rings Antique Silver 7/8" Shank Back Metal Button, Italy, 23mm # FJ-62