This has probably been hashed over in the past. I am getting ready to get back to the field, flying that is, after about a 6 month layoff. I have 3.5 gallon's of Cool Power Pro-Pattern 20% and 2 gallon's of CP 15%, on hand now.

When purchased March of this year, the LHS had to order it. Use in YS110 and OS 61 SF's. Am I OK here with this batch, or replace ?

Thanks,

Crank