Custom Truck One Source enters the second half of 2026 with the strongest operating print in its public-company history, and the investment debate now centers on whether a transmission-and-distribution rental engine, helped by a fresh two-segment reporting structure, can sustain mid-teens Adjusted EBITDA growth while net leverage continues to grind lower toward management's three-times target. The mid-year report shows record quarterly revenue and a 25% jump in Adjusted EBITDA, and the six-months OEC-on-rent yield sits at the highest reading in the company's post-SPAC era. The same report also raises the full-year revenue and Adjusted EBITDA ranges, which means the second half has to deliver more of the same, not acceleration, for guidance to clear.
The bear case lives in the cash flow line. Operating cash flow fell sharply in the first half of 2026, an outcome the filing attributes to a meaningful inventory build that funded STEM deliveries booked late in the quarter. The strong sales order backlog exited the period at roughly 3.5 months of trailing-twelve-month third-party new sales, modestly below the four-to-six month band management has historically targeted, and STEM adjusted EBITDA of $37M carried a sizable floor-plan interest expense in the quarter. The argument that the inventory build is timing rather than structural is reasonable, but the proof lands in the third-quarter print, when inventory months-on-hand should start trending toward the stated target of fewer than six.
The forward variable to track is the SER rental fleet yield, which is the cleanest read on T&D end-market intensity. The second-quarter OEC-on-rent yield sits 80 basis points above the prior year, with fleet utilization of 81.6% materially higher. Average OEC on rent is up 13.1% year over year, and each of those three metrics is at a multi-year high. The second-half setup enters with a record ending OEC. Sustained yield above 39% would cover the entirety of the raised 2026 EBITDA range on the SER segment alone, and a clean third quarter would close the remaining gap. With both metrics in place, the inventory issue would become a working-capital footnote rather than a narrative drag on the equity.
The structural change worth flagging is the move to two reportable segments, which repositions the business into Specialty Equipment Rentals (SER) and Specialty Truck Equipment & Manufacturing (STEM) and is a cleaner expression of how management now allocates capital. SER carried the lion's share of first-half segment Adjusted EBITDA before eliminations, and STEM delivered the operating leverage on volume. The transition, which took effect January 1, 2026, makes the rental business the dominant economic engine for the first time since the NESCO Holdings combination, and that reclassification is the single most important reason the consolidated revenue mix reads as more defensive than the legacy ERS/APS/TES view implied.