If your leather is too thick, 4mm - 5mm thick: Firstly, wet the leather and line up the stud parts with the hole. Press the stud into the leather to make an impression, allow leather to dry. With your knife tip pointed into the centre of the hole and laying flat against the impression, turn the leather and/or knife in a circle and gouge out a perfectly round recess into the leather to give extra depth.
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1Pc Germany Quality Soft Tape with Snap Fasteners Soft Multicolor Measuring Tape Dual Sided Tape Measure Needlework Sewing Tool
Aliexpress UK
4 Parts Colourful Cap Press Studs Snap Fasteners Handbags Clothing Jacket 15mm. S Spring Press Studs Snap Fasteners for Leather Coats Handbags Clothing 15mm. Press Studs Snap Fasteners with or without Fixing Hand Tool Leather Craft 15mm.
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10PCS Snap Fastener Metal Jeans Waist Buttons 17mm Replacement No-Sew Screw Button Repair Kit DIY Buttons Accessories
Aliexpress UK
Good quality sew-on snap buttons in various sizes.
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1.5M Soft Tape Measure Tailor's Tape With Snap Fasteners Body Measuring Double-sided Ruler Portable Needlework Sewing Tools
Aliexpress UK
Qty: 10pcs, 50pcs, 100pcs. Silver Press Studs Snap Fastener Studs Parts for DIY Leather Jacket Crafts 15mm. 15mm Press Studs Snap Fasteners Brass Heavy Duty DIY for Leather Fashion Jackets. Press Studs 4 Parts Snap Fasteners Coats Clothing Leather Jackets Purses 12/15mm.
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40pcs 14mm Magnetic Button Clasps Set - Metal Snap Fasteners for Sewing, Crafts, Wallets, Bags, Clothes, Leather
Aliexpress UK
Made of strong iron. They do not bend break or pull apart. For use on cloth or leather between 0.5mm - 3.5mm thick.
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Easy-Attach 14mm Magnetic Snap Buttons - 40 Set Multi-Color Pack for Sewing and Crafts, Durable & Stylish Metal Fasteners
Aliexpress UK
Add a touch of elegance to your leather jackets, handbags, clothing and furniture with these heavy-duty press studs. These round-shaped studs are perfect for blazers and suits. These press studs are not only functional but also add to the aesthetics of your fashion wear, clothes, and arts and crafts.
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1.5M Soft Tape Measure Tailor's Tape With Snap Fasteners Body Measuring Double-sided Ruler For Needlework Sewing Tool NEW
Aliexpress UK
Snap Poppers Button Fasteners Prong Ring Press Studs for DIY Baby grows 9.5/11mm. 20mm Snap Poppers + Fixing Hand Tool Prong Ring Press Studs for DIY Craft. Prong Pliers Ring Press Studs Snap Popper Fasteners for DIY Crafts Clothing BIBs.
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1Pc Germany Quality Soft Tape with Snap Fasteners Soft Multicolor Measuring Tape Dual Sided Tape Measure Needlework Sewing Tool
Aliexpress UK
These Spring Button Press Studs are commonly used as bag fasteners, within haberdashery and leather craft. Spring Button Press Studs. Hand Press &Dies available.A setting tool is required in order to use the item.
eBay
1Pc Quality Soft Tape with Snap Fasteners Soft Multicolor Measuring Tape Dual Sided Tape Measure Needlework Sewing Tool
Aliexpress UK