Humminbird - IDMK H5 - In-Dash Mounting Kit HELIX 5 Models - 740142-1. The IDMK H5 is an in-dash mounting kit for HELIX 5 Series fish finders. This provides what is needed to complete a secure and finished look for in-dash mounting of your Humminbird fish finder.. Features:. Compatible with: All HELIX 5 Series. This optional in-dash mounting kit is not optimized for metal dash scenarios. 1-Year Limited Warranty. WARNING: This product can expose you to chemicals including LEAD which is known to the State of California to cause cancer, birth defects or other reproductive harm. For more information go to P65Warnings.ca.gov.