The 25.7V minimum breakdown voltage gives a guard band above the standoff before the device starts conducting. The T-18 axial package (through-hole) makes it straightforward to hand-rework — the leads are robust enough to survive a hot-air desolder cycle without pad damage, and the body orientation is unambiguous.
Any remaining stock in the supply chain is last-time-buy inventory or surplus. For a BOM line that calls out this exact MPN, the only sourcing path is through independent distribution or the spot market.
Selecting a replacement or equivalent
The clamping voltage at 37.5V and the 25.7V breakdown minimum are the key thresholds to preserve in the replacement.