The set includes: 50Pcs Stainless Steel Screw Inserts + 1Pcs wrench + 1Pcs tap + 1Pcs drill bit. If it is M4 0.7 2D, the length after installation is calculated as 4 2=8MM. If it is M4 0.7 3D, the length after installation is calculated as 4 3=12MM.
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