rather useless

Due to the radially abnehnehmenden the middle cutting speed of this tool is to use only very limited. In addition, the cutter is practically not particularly shaped and mitlerweile dull.

I bought at the hardware store ultimately better glass and ceramic drills that were made cheaper and more expensive.

All drill of this type have due to their geometry course a disadvantage. If you want a durable tool by more than a plate of "push through" should look at the more expensive alternative.

A pre-drill with a much smaller diameter is also advisable.

Overall a bad buy because mostly unsuitable and buy better and cheaper at the hardware store.