Fuse of a special type SP protects electrical installations and networks from overload currents and short-circuit currents. Installed in DC electrical circuits up to 30 V. 
 
The fuse consists of a glass tube, two nickel-plated brass caps and a fusible element soldered into them. 

Fuses are electrical switching devices designed to protect electrical circuits from emergency modes, to protect electrical networks, electrical equipment from overload currents and short circuits. They disconnect the protected circuit by destroying the live parts specially provided for this under the influence of a current exceeding a certain value.

The fuses meet the requirements of TU 16-522.001-82. Climatic modification and category of placement: UHL3. 
 
The structure of the symbolic designation of SPX fuses: 
SP - special fuses; 
X - rated current, A: 1; 2; 5; 10; 15; 20; 25; 30; 40 
 
Warranty period - 5 years, including the warranty period of storage in the manufacturer's packaging no more than 1.5 years from the date of acceptance of the product by the customer's representative. Guaranteed operating time - 1500 flying hours within the warranty period.