Yes, the C406-2 & C406-2HM ELTs are a direct replacement for the 110-406 Series. According to the Discontinuance letter released from Cobham, the 110-406 series product line was discontinued on 12/31/01. Artex planned to continue providing battery packs and repairs until 2008. You can view the letter here.
According to Artex (now Cobham) the C406-2/2HM ELTs are a direct replacement in form, fit & function. Additionally, the ME-406 series is suitable for General Aviation and Light Helicopter applications. These ELTs are certified to the requirements of FAA TSO C126 and ETSO-2C126.
View the C406-2, C406-2HM, and ME-406 Series product pages for more detailed information.