Using Regular Expressions

Pattern segments:

[A-Z][A-Z] Two Letters (Uppercase)

[0-9][0-9][0-9] Three Numbers

[A-Z] One Letter (Uppercase)

Giving a Pattern:

[A-Z][A-Z][0-9][0-9][0-9][A-Z]

Good match: BX120R

Bad match: BX1204