Best Practice for Organizing Sponsored Ad Campaigns

I am a reseller of industrial supplies. I want to optimize my Sponsored Ads Campaigns and have been running Sponsored Product Ads.

I wanted to know if there is a best practice when organizing these campaigns. I sell a lot of things like fasteners and valves that have multiple sizes for one type.

Should I be creating a campaign for each product I sell? Or say if there is a stainless steel screw with different lengths, should I create a “Stainless Steel Screw” Campaign with an Ad Group for each length of that stainless steel screw I am selling.

Any suggestions are appreciated. Thank you for your time!