Is there a 12" 4 Flat Extender that will Fit in the Curt Mounting Bracket for 4 Pole Flat?

Updated 12/30/2025 | Published 11/26/2025

Question:

Is rhere a recommended 12 inch long 4-flat extension that will fit the bracket? I have a Reese extension and the plug is too large to fit the opening in the bracket

asked by: Tnf

Expert Reply:

Hello Tnf,

Since your Reese extension will not work, I would go with the Hopkins 4-Pole Loop - 12" Long # HM48145. The Hopkins has a slimmer design so it will be able to fit in the Curt Mounting Bracket for 4-Pole Flat Trailer Connector # C42CR.

What kind of trailer or accessory are you using that you need the extension?

expert reply by: Kate F

Kate F.

12/29/2025

Hey Tnf, did the Hopkins 4-pole loop end up fitting better with your Curt bracket? Knowing how it worked with your setup could help others trying to match the same parts.

Tnf

12/29/2025

@KateF the Curt 58380 4-flat wiring harness has good secure fit with the Curt bracket. I have been using it for over a month now and just completed a 1000 mile road-trip with no issues. Thank you.

Kate F.

12/30/2025

@Tnf Glad to hear it Tnf! I appreciate you taking the time to answer. Any fun stops on that 1,000 mile trip? May 2026 bring you your greatest adventures yet!