It's great to be able to have refills instead of having to buy a new marker. Just wish the refill packs came with an option to get more than 2 refills at a time. I use these extensively for my Bible as well as other books.
If you are aware of these refills, I assume you are already the happy owner of the retractable "pen." In my area (NE Ohio), good luck on finding these refills--especially if you want a quantity. The local stores are always out of some color--usually pink or yellow. If they have the pen, there are no refills. If they have the refills (usually about 3 of them) there are no pens. CBD is the answer. I can get as many pens and refills as I want, and after "pounding my head against the wall" in local stores that could not order for a single color, CBD is a blessing indeed. These are great markers/crayons, and they do not bleed through. And the service through CBD is fabulous.
These are the refills for the best highlighter I have ever used. I am a full time researcher and teacher, and an avid reader. I use these highlighters all the time, in every type of book. I will never return to other types of highlighters. These are, quite simply, the best highlighters on the market. I recommend them to everyone who asks.