#10 Regular Envelope - Astrobright - 24# Eclipse Black (4 1/8 x 9 1/2) - Business Color Series (Box of 500) A Quantity of 500 - #10 Astrobright Eclipse Black Envelope Made with 24# Astrobright Eclipse Black Paper. FSC Certified. - Regular Gummed Flap Great for statements, invoices, checks, letters, contracts, and more. This envelope may be sourced from any one of a number of top brands. Ships via UPS Ground