Windscreens, grids, waxes, connectors, desiccants. The things that run out, get lost or degrade in sunlight, and stop a campaign.
Temporary sealing during in-situ tests.
A specific consumable nobody stocks in Italy.
Dust and sea salt on the grid means high-frequency drift.
The connector that breaks at five on a Friday.
Already in block B.
Finding the same point again six months later.
The box that solves 85% of what goes wrong.
Every instrument says for itself when it was last calibrated.
The part you lose that stops a campaign.
Cases and instruments that spend the winter in a van.
One format across the whole kit instead of five.