Product Tag - purple grape lower receiver

I need you to act as a top performing seo and write me a brief 150 word description for the product tag (purple grape lower receiver) and include some of the parts they play in the firearms industry. when you are done with that i then need you to write me a 150 character meta description separate from above about the parts and use some keywords from the ar-15 industry so i dont have duplicate content for both. Include these keywords into the 100 word description (ar-15, ar-10, parts)