Safety, single sided, razor blade
Razor blade, single sided safety-type
These long-established blades are small and fiddly for general use, but very handy to include in small containers of tools. They are sharp ~ fairly safe to use ~ and inexpensive.
We find that we often use this knife in scraping or shovelling roles. The extreme straightness of the edge enables the knife to slide along a surface without cutting into it, for example when removing a spill of glue from a surface.
As with all very sharp blades these are not for sale to anyone under eighteen, and all purchasers must be careful not to let them be used by anyone lacking training and skill in the use of edge tools. It is a good idea to have ~ close to hand ~ a first aid kit with sticking plasters in it.