Which Domain Name Should I Use On Directories

Hi. I have two domain names for my website, my URL is my main key word phrase to help with optimisation, and I have another domain name which is my company name that points to my URL that’s on my website
For example
Company name: www.ESSA.co.uk (this is pointed to the one underneath)
My URL www.securityinstallatin.co.uk (this would be my main keyword)
When I list my business details on various directories which domain name should I use? I have been using obviously www.ess.co.uk as this is my company name, but am I right in thinking to get more links to my website I should of used www.securityinstallation.co.uk which is my URL for my website
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SEO|SEO UK