CMI

What they do

Cummins is the largest U.S. maker of the backup diesel generator sets that data centers fire up when the grid goes down . Diesel gensets are the proven, reliable backup standard — every gigawatt of new data center load means a few hundred megawatts of backup gensets get ordered. Quiet, slow-and-steady winner. Truck-engine cyclicality is the bulk of the business though, so the AI tailwind only partially shows up in the stock.