The pens are flexible, lightweight, safe and work well. Each pen is 4 inches long Made with a soft rubbery material that bends under the slightest pressure. Weight: 0.001 oz These ink pens are available in 24 Pack. Flexible Safety Pen is a soft and flexible pen good for schools and anywhere easy to use writing pen is needed. The pens come in packs of 24 and are available in blue and black ink. Each pen weighs approximately 0.001 oz.