Polymer suspension line insulators type LK 120/35-I are designed for securing and insulating bare and insulated conductors of the SIP-3, PZV, PZVG types on AC overhead lines with voltages of 35 kV and frequencies up to 100 Hz, operating in ambient temperatures from -60 °C to +50 °C. The climatic version and placement category are UHL 1 according to GOST 15150. The insulator design allows for the installation of arc protection devices UZD-3 or UZPN directly onto the end fittings. Manufactured according to TU 3494-005-57966314-2006, these insulators comply with GOST 28856, GOST R 55189, and IEC 61109 standards.