DL3 is a NiZn ferrite with an initial permeability (μi) of approx. 350, a saturation flux density (Bs) of approx. 350 mT at 25 °C (280 mT at 100 °C) and a Curie temperature above 200 °C. Its medium permeability combined with a high resistivity of about 10⁷ Ω·m keeps the relative loss factor very low under low flux (15×10⁻⁶ at 0.1 MHz / 30×10⁻⁶ at 2.0 MHz), minimising signal distortion and insertion loss, while its excellent thermal-shock resistance withstands the rapid temperature swings of reflow soldering — well suited to SMD parts. Typical uses are wideband and balun transformers, common- and differential-mode EMI suppression, RF tuning elements, mid/high-frequency low-power inductors and RF chokes, as well as precision sensing cores such as automotive ABS sensors. Within the DL family, DL3 is the general-purpose baseline: choose DL4 (μi approx. 600) for higher sensitivity, DL5/DL6 for higher flux density and temperature capability, or DL5H to balance both.