Factory supply DIY making badge findings metal butterfly clutch pin back lapel pin backs

have to make 10000 pin badges for a client.... have mild steel disks but need the backs as above. What else do I need to attach the back to the disk... the disk is mild steel 17mm diameter x 1mm height
Material:metal
Type:Brass
Product Type:Badge & Emblem
Technique:Plated
Style:Antique Imitation
Use:Art & Collectible
Theme:Angel
Regional Feature:Europe
Place of Origin:CN;GUA
Brand Name:Jialin
Name:Butterfly Clutch Pin Back
Shape:Round
Nail Size:9mm*10mm
Clutch size:11.4mm*6mm
Color:nickle
MOQ:5000 pcs Butterfly Clutch Pin Back
Supply Ability:100000 Piece/Pieces per week collar Pin
Packing:5000 sets
Package:OPP bag