It may be difficult to open the pump the first time. Before inserting in the acrylic paint, to easily open the pump, hold the area containing the spring, and turn in the direction indicated on the spout.
If clogged, you can dislodge the dried, flexible paint with a paper clip, tooth pick, or small piece of wire. The pump can also be cleaned out by soaking in soap and warm water then keep pressing the pump. If not effective, allow the pump to soak overnight. Finish by rinsing thoroughly.
When Open: 13.5 inches
When Closed: 12.75 inches
Tube measures: 8.75 inches