This simple device facilitates the use of any tube, helping to squeeze it evenly and gently. It consists of a base in a hole which is inserted the tube, and turning a key with slit for exciting a planar end of the tube. The base and key are made of wooden bars of appropriate dimensions. Their interaction is clear from the figure.
Recommend to read
KNIFE ROLL
The coil is the most convenient form of packaging thin sheet materials and for the transportation and storage in warehouses. Foil, a synthetic film or paper in a tightly collapsed become a...
WITH CARDS IN THE AIR
Informing about the occurrence of an event, people often use sound signals. Usually they have the character of a continuous sound "one note" annoying "beep-beep" or howling siren with a...