Two similar names. Two unrelated businesses.
Centennial Defense Systems, Inc. is a Colorado Springs software company identified by CAGE 20CQ3 and UEI NLVSULN86UB9. It is not affiliated with centennialdefensesystems.com, the unrelated firearms-parts retailer.
This company
Centennial Defense Systems, Inc. — software: local-first evidence tooling (Archivist, Archivist Sort), open agent-evidence code (Deponent), and public technical standards. Canonical site: centennialsystems.com. Identifiers resolve to official records on the verification page.
The other business
The retailer at centennialdefensesystems.com sells firearms parts. It is a separate business with separate ownership. Nothing on this site describes it, and nothing on its site describes this company. No criticism of that business is implied — the names are simply close enough to confuse search engines and people alike.
How to tell them apart
If a page carries CAGE 20CQ3, UEI NLVSULN86UB9, Colorado Springs software, or the domain centennialsystems.com, it refers to this company. If it sells firearms parts, it does not.