I am always instant liquid glueing something and alway have it on hand. Usually I buy a multi pack at the dollar store as they seem to be a one time use. You can not see the inside of this Gorilla glue pen, all you see is the top of what looks like a standard glue tube that you screw the cap onto. I am not sure how it efficiently it uses the inner tube of glue. I might disassemble once its finish and post the pictures:) After 4 separate uses there is still no clogging. You also have no idea how much glue is left in the pen. This pen is easy to hold, especially for me since I have arthritis in my fingers. However, it is easy to accidentally hit the big orange button, or press it too hard and you have glue coming out fast when you open the pen. We tried this glue on a broken tip of a delicate expensive ceramic statue. Glue was everywhere, next thing we know our fingers are sticking to the statue. You barely need to apply pressure to the button to get the glue going! When the ceramic piece stuck, it wasn't lined up properly, which is not the pen's fault, but you have to be aware that even tho this works on many surfaces, which is great, the dry time varies up to a minute or so. I also repaired a rubber casing around our marine power plug, it was just the exterior casing not the wires. It took several minutes to hold. I will have to update this at a later point as its used most weekends. I do wish you could buy replacement glue cartridges for this pen. The glue tube looks small so it's expensive for what you get. Just be careful not to accidentally use too much. Bonding appears to be strong, but it might take a minute to hold to certain surfaces. One great thing is this works on almost all surfaces, unlike Crazy Glue, that you buy it for specific surfaces like ceramics, or wood or plastic. The glue is not a gel but slightly thicker than typical liquid instant glue. Other packaging of Gorilla Super Glue may be a better value.