These disposable comedos knives/comedone needles are made for the stainless steel comedone knife handle by Erbe (ERFC3-1). The needle is specifically made for removing blackheads the needles will make extracting the oil blackhead and all easy and efficient. All of the needles are made out of stainless steel which are anti-rust and anti-allergic. The needles are also intended for sterilization so there is no worry of infection. Purchase these needles with confidence knowing that Erbe doesn't compromise on quality even when it comes to disposable products.