Best marine sealant for thru hull txducer?

[landingzone]

What is the best marine sealant for a thru hull transducer? I'm installing one on my 270AJ and I don't want any leaks! Any other install advice is welcome also.

Thanks, Dick

[mudflat]

Here's a link that Jim at BOE Marine has on installing an Airmar thru hull

They make it look easy

He recommends using 3M 4200

[landingzone]

Wow! Thanks Mudflat. That video is excellent. It gives several good suggestions and they are installing the exact same transducer that I will be.

[seasquirrel]

3M 4200 Good stuff