('Bolt List'!$H$9:$H$188="1") This part was added to the formula below to
introduce one more criteria and it does not work at the moment but it did
before the extra criteria.
column "H" could be empty or it could have numerical value, the value has no
importance but the formula needs to recongnise an entry.

Can anyone help with this formula?

Thank you in advance.

Serge

=SUMPRODUCT(('Bolt List'!$D$9:$D$188=K8)*('Bolt List'!$J$9:$J$188=L8)*('Bolt
List'!$E$9:$E$188="A325 Black.")*('Bolt List'!$H$9:$H$188="1")*'Bolt
List'!$C$9:$C$188)