Adjustable Pickup Mounting With Threaded Inserts in Instrument Building Posted February 4, 2018 · Report reply I went looking for these at home depot and although it says they had some in stock, I was unable to find them. So then I went to ace (god I love ace) and found similar. #4 4-40 threaded inserts. This type has flat head screwdriver grooves at the top and threads into the body as opposed to expanding. I believe they were $.60 ea and the #4 1" brass screws I bought were $.33 ea. Just wanted to let those in need know.