Free Edition:
http://download.piriform.com/ccsetup531.exe
Portable:
http://www.piriform.com/ccleaner/download/portable/downloadfile
Professional Edition (Old Setup UI):
http://download.piriform.com/pro/ccsetup531_pro.exe
Professional Edition (New Setup UI):
http://download.piriform.com/ccsetup531pro.exe
Technician Edition:
http://download.piriform.com/te/ccsetup531_te.exe
Business Edition:
http://download.piriform.com/be/ccsetup531_be.exe
Business Edition MSI x64:
http://download.piriform.com/be/ccsetup531_x64_be.msi
Business Edition MSI x86:
http://download.piriform.com/be/ccsetup531_x86_be.msi