Toyota

ARP are a manufacturer of fasteners / bolts found in engines and drivelines, ranging from OEM replacement parts to specialty hardware for racing applications.
ARP is the world leader in fastener technology.
ARP Pro series connecting rod bolts are precision CNC-machined to exacting specifications and designed for optimum reliability. They are heat-treated and threads are rolled to provide up to ten times more fatigue strength. This makes them far superior to standard OEM fasteners in terms of durability, and fully capable of handling the extra stress of high-combustion engines.