4 Amp Fuse, 5x20mm 250V Fast-Blow Glass Fuse, F4AL250V, 10 Pack | Fast-Acting 4A Protection, UL Recognized, Visible Glass Body, Nickel-Plated Brass Caps

4 Amp Fuse, 5x20mm 250V Fast-Blow Glass Fuse, F4AL250V, 10 Pack | Fast-Acting 4A Protection, UL Recognized, Visible Glass Body, Nickel-Plated Brass Caps

• 【Ratings & Materials】Each F4AL250V fuse measures 5×20mm (0.20" × 0.79") and is rated 4A, 250V with an F fast-acting response. The glass tube helps with visual inspection; nickel-plated brass caps resist oxidation at holder contacts, the alloy fuse element provides the intended opening response, and tin-plated copper internal leads support dependable conductivity.
• 【Fast-Acting Response】The F-type element interrupts excessive current quickly in circuits with limited startup surge, helping reduce prolonged overcurrent exposure. It is not interchangeable with a T-type time-delay fuse, which is designed to tolerate normal inrush from motors, transformers, compressors, or other surge-producing loads.
• 【Correct Replacement】Disconnect power, remove the failed fuse, and seat the new 5×20mm cartridge firmly in the holder. Match the original 4A current rating, 250V voltage rating, physical size, and F fast-blow type; verify the holder is correctly rated and never install a higher-amperage fuse to stop repeated opening.
• 【Specified Applications】Current rating alone does not determine compatibility. Equipment that may specify a 4A fast-blow cartridge includes bench power supplies, paging amplifiers, stage lighting, laboratory instruments, and powered equipment controllers. Confirm the fuse marking or service manual states 4A, 250V, 5×20mm, and F-type before installation.
• 【10-Piece Pack】Includes 10 matching F4AL250V fuses with UL Recognized for repair, scheduled maintenance, and backup inventory. Keeping identical replacements on hand helps avoid substituting the wrong current rating, physical size, or response type during service.