diff --git a/src/backend/vector/avx2/field.rs b/src/backend/vector/avx2/field.rs
index e7ee91688..7fbae6548 100644
--- a/src/backend/vector/avx2/field.rs
+++ b/src/backend/vector/avx2/field.rs
@@ -856,8 +856,8 @@ impl<'a, 'b> Mul<&'b FieldElement2625x4> for &'a FieldElement2625x4 {
         //  z5 < ( 1 +  1   +  1   +  1   +  1   +  1   + 1*19 + 1*19 + 1*19 + 1*19 )*2^(51 + 2b) =  82*2^(51 + 2*b)
         //  z6 < ( 2 +  1   +  2   +  1   +  2   +  1   +  2   + 1*19 + 2*19 + 1*19 )*2^(51 + 2b) =  87*2^(51 + 2*b)
         //  z7 < ( 1 +  1   +  1   +  1   +  1   +  1   +  1   +  1   + 1*19 + 1*19 )*2^(51 + 2b) =  46*2^(51 + 2*b)
-        //  z6 < ( 2 +  1   +  2   +  1   +  2   +  1   +  2   +  1   +  2   + 1*19 )*2^(51 + 2b) =  33*2^(51 + 2*b)
-        //  z7 < ( 1 +  1   +  1   +  1   +  1   +  1   +  1   +  1   +  1   +  1   )*2^(51 + 2b) =  10*2^(51 + 2*b)
+        //  z8 < ( 2 +  1   +  2   +  1   +  2   +  1   +  2   +  1   +  2   + 1*19 )*2^(51 + 2b) =  33*2^(51 + 2*b)
+        //  z9 < ( 1 +  1   +  1   +  1   +  1   +  1   +  1   +  1   +  1   +  1   )*2^(51 + 2b) =  10*2^(51 + 2*b)
         //
         // So z[0] fits into a u64 if 51 + 2*b + lg(249) < 64
         //                         if b < 2.5.