S1
S1 means rust, roughly the size of a fist.
錆
sabi
rust
Rust the inspector could see and put a boundary around. On the diagram it usually lands on a wheel arch, a sill, the bottom of a door or the underside.
Rust on a sheet is always the visible edge of something larger. Metal corrodes from the inside of a seam outward, so the fist-sized patch he marked is the part that has already broken through.
Where an S sits matters more than how big it is. Rust on a wheel arch is a panel repair. Rust on a sill, a chassis rail or a subframe mount is structural, and it is the one honest reason to walk away from a car that otherwise reads well.
What it should do to your bid
Never bid the low end of a rust estimate. Rust is the one mark where the sheet reliably understates the work.
Night Line
Reading a sheet with S1 on it?
The free Decode is not open yet. Leave an address and we will write once when it is, so you can put your own sheet through it rather than reading ours.