U-fill: The world’s only reusable glue stick range. The ‘Blue Stick’ is a training glue stick designed with the optimum adhesive content and setting time for younger children. Applies bold blue to help them see where they are sticking, then dries clear. Once used, do not throw away your empty glue sticks. Instead, replenish the contents with our ‘U-fill Blue Stick Refills’. Box of 10.