When these arrived, I tried to use them only to find out that the black was dried out. This was definently an issue, so I contacted customer service. Within the same day, I had received an email back stating that the cost of the markers would be refunded to me without me needing to return the product. While this is not an ideal solution, the seller was nice and very quick to work with me to make me happy, so it does bear sharing. The other markers had nice bright colors with both thick tip and a fine tip on each marker. They work really well for adult coloring books because they can be used in small areas using the fine tip, and then color the larger areas with the broad tip.