Thank you for viewing. [Size] Total length: Approximately 14.6cm, Nib thickness: 1.0mm This is a black ballpoint pen. The ballpoint pen refill is replaceable. When the ink runs out, remove the old refill and insert a BIC Crystal Medium 1.0mm ballpoint pen refill (as shown in the last photo) to use it again and again. You can purchase refills on Amazon, etc. Made of heat-resistant glass using a special processing technique, this is an original, one-of-a-kind piece with a unique design. Please be sure to check the photos. If you have any concerns or questions, please comment beforehand. Also, if you like it, please consider following me. #lampwork #burnerwork #glassart #tonbodama #tools #glasswork #boroglass #borosilicate glass #glasswork #heatresistantglass