and this:

The 6"x1" with caps use epoxy to hold the quartz inside and the caps add to protect the rods if dropped. If you drop the 4"x1" without caps you may damage the rods. I believe those expensive rods are 6"x1" which is the same size the pharaohs used. However the pharaohs also used them while standing barefoot on the earth(grounding) and gazing into the rising/setting sun so the body can access 3 sources of energy. I made a video showing how they work see link below.