I have a Nortel networks NT8B27JAAA AO993448 T7316E REL:02 2004/09/20 2006/03 CHARCOAL NNTMENT62245 I know the color has nothing to do with it, but I thought I would be thorough and give you all the info on the underside of the telephone. question: our office has no manual and I can't find model that matches this. I need to adjust things and time but have no instructions. please help. alessandro.cigni@tax.hrblock.com