Two Peas and Their Pod. IMPORTANT HEALTH NOTE: Avoid pressure treated wood with CCA-chromated copper arsenate (arsenic), as you don't want arsenic leaching into your soil. There are other pressure treated - non arsenic - woods available.
49 Brilliant Garage Organization Tips, Ideas and DIY Projects - Page 31 of 49 - DIY Crafts. This looks like Bouillon Cube jar lids screwed to the board, so jar part can screw onto the lid. I've also seen done with baby food jars.