I have found that square bottles with ribs won't collapse as easily and don't require a support ring. Here are some photos of one I just assembled. Start by carefully cutting off the bottom of a plastic drink bottle (64 oz). The bottle should be big enough so you can fit your entire closed hand inside Use some sand paper to smooth the sharp edge of the plastic and correct any unevenness. The key to a well functioning vapor lung is a well made bag. Tape tabs will keep the bag in a well functioning position. Cut a piece of packing tape 5" long and place it 1-3/4" from the closed end of a 1 gallon zipped food storage bag. Cut 3 more pieces of 5" long tape and position as shown. Place a piece of tape that is 6" long in the very center. Fold each of the pieces of tape in half so that there will be 4 tape tabs that are 3/4" long and the one in the center will be 1-1/4" long. Cut the zip part off from the food storage bag. Cut a piece of tape 3" long and place it on one corner of the open end of the bag. Fold the tape so it closes off that portion of the open end. Place the bottle fully inside of the bag which will allow you to tape the other corner of the open end of the bag with another 3" long piece of tape. Start pulling the bottle out of the bag. There is a very tight fit between the bag and the bottle now. Position the bag on the bottle so that it is about 7/8" from the end. The taped corner will fold back onto the bag, so position the bag such that the folded portion is in the center of the bottle when it is taped on. Before taping the bag to the bottle, it helps to finish taping the bag for the pull tab. Fold the bag starting from the sides so that the tabs align. Cut pieces of tape 3/4" long to make thin strips and tape the tabs together by the sides. Repeat for the other side of the bag. Now tape the center tab to the 2 outer tabs using more thin strips of tape. Place one more piece of 6" long tape over the entire tab assembly to tie everything together and provide a pull tab. Cut some shorter pieces of tape to secure the bag in 4 locations. Tape the corners where the bag folds to hold it in place. Use one long piece of tape to go all the way around and seal the bag to the bottle. There is no tape inside of the bottle or bag. The vapor only sees the poly inside of the bottle and bag. I didn't take a photo of the cap as it would depend on the vaporizer to which you are connecting. In my case, I drilled a 10mm hole for a 10mm glass mouthpiece tube. Start with a small drill bit and then just work your way up in size. After the 3/8" drill bit, I wrapped a 5/16" drill bit with some sand paper and worked on the hole until the 10mm glass tube would just fit. I don't want to use any tape in the vapor path so the hole has to be just right. Hope this helps others to enjoy the VL as much as I do.