Block from U+A4D0 to U+A4FF. This block was introduced in Unicode version 5.2 (2009). It contains 48 codepoints.
The Wikipedia provides the following information on block Lisu:
Lisu is a Unicode block containing characters of the Fraser Lisu alphabet for writing the Lisu language. The Fraser Lisu alphabet (and by extension the block) consists of glyphs resembling capital letters in the basic Latin alphabet either in their standard form or turned upside down. (The addition of the block was subject to significant debate as to whether an entire block was necessary for the alphabet or if the turned letters not already in Unicode could instead be added under the Latin script section. Ultimately, the former approach was taken, and the Lisu letters are thus semantically different from their Latin counterparts.)
This block is supported by a few fonts including DejaVu Sans and Segoe UI (since Windows 8).