Hello, this is a Cisco 2851 Router, working perfectly. Mounting brackets included as in picture.

I have refurbished it adding more RAM (now it's 512MB), more disk (128GB) and installing latest best firmware, which is c2800nm-adventerprisek9-mz.151-4.M1.bin; it runs seamlessly, although fans are a bit loud (temperatures are perfect).

This router is perfect to face CCNA, CCNP, CCIE enterprise exams and several others. It can manage easily multiple encrypted tunnels, DMVPNs, multicast, large NATs without losing speed, it used to manage the entire connectivity of a small mountain valley :)
Of course it's still good for production!

I am selling it at a ridiculous price because I need space.
Happy bidding!