The Choi implanter pen originated from the National University in Korea, the idea behind this technique is simple and combines making channel incisions sited in the recipient area and implanting the extracted follicles in one process. A Choi implanter pen is a pen-like device with a hollow needle at the tip and it is connected with a tube and a plunger. The doctor loads the follicles extracted from the donor region into the implanter pen, the follicles are put gently, using tweezers, inside the hollow needle (at the end of the implanter pen). Then the pen is used to implant the preloaded follicles into the scalp, the doctor inserts the needle at an appropriate angle into the scalp (making a channel incision site) and implants the follicle by pressing down on the plunger. This process is then repeated to implant one graft at a time.

During a typical transplant procedure, the doctor performing the procedure and the medical team working with him/her use about six implanter pens alternately to get the best transplant result in a timely manner. Each of these implanter pens is equipped with various sizes of needles to fit single, double and triple hair follicle units. With DHI, there is no need to open channel incisions. The doctor can now inject the follicles directly into the recipient area without the need to open the channel incisions, reducing trauma and bleeding during the hair transplant procedure. In addition, this technique results in faster healing for patients.