An emissions-control device on internal-combustion vehicles whose interior honeycomb is rich in platinum, palladium, and rhodium — making it the most-stolen scrap item in the US.
## What is a catalytic converter?
A **catalytic converter** ("cat") sits in the exhaust system of a gas or diesel vehicle and converts harmful exhaust gases into less-harmful ones via a coated ceramic honeycomb. That coating contains **platinum (Pt), palladium (Pd), and rhodium (Rh)** — three of the most valuable precious metals on Earth.
## Why it dominates compliance conversations
- A stolen cat sells for $50–$1,200 depending on the vehicle.
- All 50 states now have catalytic-converter–specific laws on top of general nonferrous rules.
- Most states require **VIN documentation, vehicle ownership proof, and a separate cat-converter logbook** with daily upload.
## Common state requirements (varies by jurisdiction)
- Proof of vehicle ownership (title or registration).
- Photo of the cat with a unique ID.
- Hold period of 5–30 days before resale.
- Cap on cash payouts (CA: \$0 cash, check/ACH only).
## How WeighPay handles catalytic converters
WeighPay's converter module enforces the operator's state-specific workflow, photographs the unit with a unique ID, applies the hold period, and uploads to LeadsOnline / CalRecycle nightly.