It clamps transients at a minimum breakdown voltage of 14.3V and handles 1500W peak pulse power. The DO-201AD axial package suits through-hole board layouts where a replaceable, high-surge component is preferred over surface-mount.
Obsolete — sourcing reality for the 1N6275A
onsemi lists the 1N6275A as Obsolete. No official successor is cited. The base product number 1N6275 shares the same die and package; the 'A' suffix typically indicates a tighter tolerance on breakdown voltage. If your application can tolerate the standard tolerance, the non-A variant may be a drop-in alternative — confirm the clamping voltage spec against your design margin.
For shorter pulses (e.g. 8/20 µs), the diode can absorb significantly more peak current; for longer transients, derate accordingly. This rating sets the upper bound on the surge energy the diode can clamp before failure. Operating temperature range -65°C to 175°C covers military and industrial extremes. The junction temperature limit of 175°C means the device can sit in a hot enclosure or near a heatsink without derating the pulse capability, as long as the average power dissipation stays within the package limits.