Littelfuse 229/230 series Slo-Blo® Fuses are available in 2AG size cartridge or axial lead form, offer tripped fuse indicating option, and offer features designed to meet rigorous Telecom industry requirements. 229/230 series product ordered with the tripped fuse indicating option show discoloration of the glass body immediately after trip. They offer the same performance characteristics as standard product, and help to reduce time locating the tripped fuse and troubleshooting circuit issues. The 229/230 series 0.25A - 1.25A range combines conventional over current protection with ability to withstand high current, short duration pulses which complies to short circuit requirements of UL 60950 for telephone equipment. Insulating sleeve option is also available.