I have shown this in different threads but, thought I'd drop it in a thread of its own in case it can help someone out. I cut four different angles on the 'sides' of a block of 4x4. I then glued a mirror to the 'face'. This give me a hands free reflected view for machine setups, checking inside of assemblies or under tools/cabinets. Here I use it to see an otherwise hidden witness mark (exaggerated here for clarity) while making a bit of trim for a tool stand. The metal roller doo-jobber screwed to the back is for ballast as I found it a bit tippy when in use on unstable surfaces. I suppose magnets might be a nice feature to add-on.
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