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5pcs Dot Matrix Lcd Module Display Monitor White Backlight Adapter Pcb 84*48 84x48 5110 Screen For Arduino Controller 3.3v - Lcd Modules - AliExpress
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arduino - What are these spots on the PCB that are by the mounting holes? - Electrical Engineering Stack Exchange
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Hot Sale Small Size 360degree Beam Angle Dots-Free & Uniform Light Silicon Profile for 10mm PCB Strip - China LED Neon Profile and Bendable PMMA LED Profile
![What are these dark spots around my PCB trace, and should I worry about them? I tried to remove them with 99% IPA and a brush, but they won't come off. : What are these dark spots around my PCB trace, and should I worry about them? I tried to remove them with 99% IPA and a brush, but they won't come off. :](https://external-preview.redd.it/HqhvwxPWa4m3BRxgaJfjSBEx7DW69ICcf13q_EYutqU.jpg?auto=webp&s=48118beaa2cf6c80cae4ffd629de8bef9b7e4e1f)