Just a stencil taken from a picture. The file seems a little small at 100% but you can adjust it. If you use the picture file in cura, make the lighter higher, make the base close to zero or zero, and then using the Z axis, push it down into the bed to make the holes actually holes. Or if you know a better way, do it that way. that's just what i did. Also, i didn't need all the layers. I stopped mid way through printed and it works great.
weathering stencil 3D Models to Print - yeggi
Airbrush stencil ST-AIR001-weathered-paint-1.48-paint-hobby
Free STL file Airbrush Stencils 🎨・Design to download and 3D
airbrush stencils 3D Models to Print - yeggi - page 10
airbrush stencils 3D Models to Print - yeggi
airbrush stencils 3D Models to Print - yeggi - page 10
airbrush stencils 3D Models to Print - yeggi
LIANG 0001 WEATHERING AIRBRUSH STENCILS TOOL FOR 1/35 1/48 1/72
3D Print Arm Thicken Thigh Upgrade Kit For DX9 Devastator/MFT Devastator. 1x Airbrush Stencils for 1/35 1/48 1/72 Scale Model(option). Model-004 LED
Weathering streaking Wet Paint crack Airbrush Stencil For 1/35 1/48 1/72 Model