ANY of the ones I have bought ANY WHERE, all have a "metal" tube, much a toothpaste tube and even unpunctured, they still dry out/get rock hard. But, I've also been using super glue gel made for plastic modelers and even after 6 months, they don't dry out provided care is taken in not opening them until needed. They come with a plastic tip that I open with a sewing needle, plastic screw on cap and a very, VERY small hose to insert partially into the bottle tip which you cut to length needed. When done, remove and toss the hose. You get something like 3-4" of tubing. When using this stuff, make sure the tube tip is absolutely clean when done, other wise you'll get a glue build up and before too long the cap won't be able to fit/make a tight seal, you got a rock hard bottle.