To find 1 or 2 digit hex values, use \xhex

Example

To find the escape character (which is decimal 27, hex 1B) and remove it, use the following in FuzRegex (www.fuzregex.com):

Find:       \x1B
Replace:    ^$

For low ascii use set notation [\x00-\x1F] and for high ascii use [\x7F-\xFF].