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Rules and technology in the catalog
Short explainers for tariffs, safety rules, sanctions, and the battery words that show up on car pages. Each page cites its sources.
Trade and legal rules
Chicken Tax
The chicken tax is a 25% U.S. duty on many imported trucks. It dates to 1964 and is separate from later tariffs.
25-Year Import Rule (Show or Display)
The 25-year rule and Show or Display are two different NHTSA paths. They are not the same exemption.
FMVSS and EPA Compliance
FMVSS is the federal vehicle safety rule set from NHTSA. EPA rules cover emissions. One approval does not replace the other.
Registered Importer
A Registered Importer is a business NHTSA registers to import certain nonconforming vehicles and bring them into conformity.
Section 301 Tariffs on Chinese Cars
Section 301 is a U.S. trade statute. A 2024 USTR notice set a 100% additional duty on Chinese electric vehicles in HTS 8703.80.00.
Connected-Vehicle Ban on Chinese and Russian Software and Hardware
A Commerce BIS rule restricts some connected-vehicle hardware and software with a sufficient nexus to China or Russia.
CKD and SKD Kit Assembly
CKD and SKD are industry names for unassembled and partly assembled vehicle kits. U.S. duty follows the HTS classification of the shipment.
Kei Cars
Kei cars are a Japanese small-vehicle class. That class is not a U.S. exemption from FMVSS or EPA rules.
Right-Hand Drive in the U.S.
Right-hand drive means the steering wheel is on the right. This page did not find a federal ban on that layout.
Sanctions (OFAC, North Korea and Iran)
OFAC prohibits most imports of Iranian-origin goods and most imports of goods from North Korea. Other OFAC programs are separate.
Vehicle technology
Semi-Solid-State Batteries
A semi-solid-state battery uses both solid and liquid electrolyte. Makers and papers do not all use the name the same way.
Solid-State Batteries
In a solid-state battery the electrolyte is solid. It replaces the liquid electrolyte used in a conventional lithium-ion cell.
LFP vs NMC Batteries
LFP and NMC are two lithium-ion cathode chemistries. The letters name the metals in the cathode, not a vehicle class.
Blade Battery
BYD's Blade Battery is the company's long lithium-iron-phosphate cell. Safety figures below are BYD's account of its own tests.
EREV vs PHEV
A PHEV plugs in and has an engine. An EREV is a series plug-in: the motor drives the wheels and the engine makes electricity.
800V Architecture
An 800-volt architecture runs the traction battery and drive electronics near 800 volts. Porsche describes what that voltage does on the Taycan.
Battery Swapping
Battery swapping replaces the pack at a station. NIO describes networks for charging and for battery swap.
CLTC vs EPA Range
CLTC and the EPA tests are different driving cycles. A CLTC kilometer figure is not an EPA mile figure. This page does not convert one into the other.