The liquid inside the case is made of harmless natural materials, and each one is manually sealed in Germany. There are some individual differences in the measurement time for each product depending on the ambient temperature, the size of each bead, and the color.
The case is made of durable acrylic and is hard to break and waterproof, so it can be used in various places such as kitchens and bathrooms. The measurement time varies depending on the design, and some can measure from several minutes to 30 minutes.
In Japan, it is sold by Luclan, the sole distributor, and you can purchase seven types, including a desktop type, a key chain type, and a type in which grains fall "from top to bottom". Prices start at 1,800 yen for the key chain type and 2,400 yen for the desktop type (excluding tax). There are up to 8 color variations, and it seems to be appreciated as an unusual gift.