Tile, Round 1 x 1 with Bar and Pin Holder

Many of these parts can be found with a mold defect known as a sink mark. A sink mark is an area of the part that is recessed from the rest of the part due to uneven cooling while the part is in the mold. The sink mark on this part can appear as anything from a single location on the surface around the bar that is indented to a complete sunken ring around the bar.