They are made of compressed turf. Soak each pellet in water for a short period of time (20 minutes) and they will enlarge up to 7 times their original size. Ideal for rooting and cuttings. Box of 2000 coco disk.
The Jiffy Medium 36mm (2000 / Cs) is evocative, to say the least, but that's why you're drawn to it in the first place.