This is the first time I have uploaded a model this complex with more than one material to sketchfab. I am not quite sure how to transfer the materials from Blender to Sketchfab, here is the result.
Here is a vintage microphone I created following a tutor4u tutorial on youtube. It turned out rather well, which makes me feel better about my modeling skills.
Below are a few renders directly from blender. I feel they look better than the sketchfab upload. The lighting and materials look brighter and more realistic, showing how the microphone should look.