3-part ladder with rungs, usable as both a standing and sliding ladder, providing insulation up to 1000 V AC/1500 V DC. This combined three-part ladder can be used as a standing ladder or as a leaning ladder. When used as a standing ladder, the third upper section serves only as a safety bridge. It offers optimal stability through a base traverse, and the sliding ladder is height-adjustable from rung to rung by hand. It features two wall-running rollers at the top of the ladder, an aluminum locking and opening mechanism, high-strength tension straps to prevent accidental opening of the standing ladder, and hollow fiberglass-reinforced plastic (GRP) beams in an H-profile (90x32 mm, 70x32 mm for 8 rungs). The aluminum rungs measure: rung cross-section 27x27 mm, rung spacing 280 mm, and it is tested according to EN 131 (except for the 3x14 rungs!). Number of rungs: 3x12. Height of standing ladder: 3.50 m. Maximum height of sliding ladder: 8.85 m. Weight: 38 kg. This ladder is made of plastic with tested, extremely weather-resistant fiberglass beams that provide electrical insulation, specifically designed for professional users working near cables, connections, or other live electrical installations. It is lightweight and easy to handle due to the special design of the GRP beams (hollow or C-profile) and aluminum rungs or steps, with rungs and steps permanently double-riveted to the beams. Rung spacing is 280 mm, with a load capacity of 150 kg, and a slip-resistant stand provided by rubber ladder shoes. It includes detailed operating, assembly, and safety instructions. The ladders comply with the European Standard EN 131 and electrical tests according to DIN 53 481, 53 482, and 53 483 conducted by the independent testing institute C.E.S.I., with a 5-year durability guarantee.