These have a single flute with a deep cavity to carry a lot of material out of the cut. It's like digging with a shovel that can hold much more dirt.
These end mills are designed mainly for plastic but will work with wood and it is surprisingly more quiet than the two flute end mills.
This end mill will create a flat bottom surface
Cut Diameter: 1/4 inch (6.35mm)
Shank Diameter: 1/4 inch (6.35mm)
Cut Length: 1/2" (13mm) and 1" (25mm)
Overall Length: 2" (50mm)