Plastic pourers in Black color. Also available in florescent red, green, white, blue and yellow. To properly seat pourers, push fully into the bottle, then pull up until the sealing splines reverse direction.
To keep the pourers sealing properly, they should be removed from empty serving bottles and placed in hot water for cleaning.
The hot water softens the plastic sealing splines and allows them to return to their original shape.
Economical and last for years. Pack of 12.