I found these when I was kickin' it at my local WM. These are single edge razor blade holders made of plastic. I bought these cause I was wiping out my supply of x-acto blades just trying to cut photo etch stuff so I bought these with the idea of being able to replenish blades in bulk fairly cheaply.But I also found another bonus with them especially if you have kids that sometimes get into things on your workbench.If you will notice these blades are placed securely in the holder and when you get done you can turn the blade around dull side out when you get finished using it.(the one on the left has been 'safed'.I paid less than a dollar for each one.And I found them in the house paint section. I thought they would come in handy for other folks so I thought that I would pass it along. Stay safe ! Later,Scot