Echo SRM-2620ES Manual De Instrucciones página 16

Before you start
Fuel
Fuel supply
 Recommended mixture ratio; 50: 1 (2%) for ISO-L-EGD
Standard (ISO/CD 13738), JASO FC,FD grade and ECHO
Premium 50: 1 oil.
 Do not mix directly in engine fuel tank.
 Do not add so much fuel that it reaches the mouth of the fuel
tank (A). Keep the fuel within the prescribed level (up to the
shoulder level (B) of the fuel tank).
 Tighten the fuel tank cap securely after refuelling.
14