Stonebench

Stonebench connects companies that need custom parts made with the factories that can make them, and handles the messy middle, quotes, quality, logistics, that usually turns sourcing into a months-long ordeal. Upload a spec, get real bids from vetted shops, ship.

We backed Stonebench because they solved the trust problem first. Manufacturing marketplaces live or die on whether the buyer believes the part will arrive right, so Stonebench built the inspection and guarantee layer before chasing volume. That order of operations is everything.

The unfair edge is liquidity on the supply side, the vetted factory base that took years to assemble and cannot be cloned overnight. Once both sides show up reliably, the flywheel spins on its own. By Series B the repeat-order rate told us the flywheel was real, and that is when we leaned in harder.