▶ A tɛ̈n tɔ̈u tɔ̈u tɔ̈u tɔ̈u tɔ̈u tɔ̈u tɔ̈u tɔ̈u tɔ̈u tɔ̈u ▶ Fully wrapped valve seat design, with superior anti-expansion and anti-pollution capabili