Hello,
Please Download the below Installation files.
1) Symantec_Endpoint_Protection_12.1_RU1_Part1_Installation_EN.exe
2) Symantec_Endpoint_Protection_12.1_RU1_Part2_Tools_and_Documents_EN.exe
Symantec_Endpoint_Protection_12.1_RU1_Part1_Installation_EN.exe includes all the Installation of SEPM 12.1RU1 , SEP 12.1 RU1 32 bit , SEP 12.1 RU1 64 bit, SEP MAC 12.1 RU1 , SEP 12.1RU1 Linux
whereas
Symantec_Endpoint_Protection_12.1_RU1_Part2_Tools_and_Documents_EN.exe includes Tools and Documents for SEP 12.1 RU1
The other installations like below are single installations provided for convenience, so that they can be downloaded easily and seperately as their size is less (compared to the above full download)
Symantec_Endpoint_Protection_12.1_RU1_Win32-bit_Client_EN.exe 12.1 RU1
Symantec_Endpoint_Protection_12.1_RU1_Win64-bit_Client_EN.exe 12.1 RU1
Symantec_Endpoint_Protection_12.1_RU1_SEPM_EN.exe 12.1 RU1
Symantec_Endpoint_Protection_12.1_RU1_Mac_Client_EN.zip 12.1 RU1
Symantec_Endpoint_Protection_12.1_RU1_Linux_Client_EN.zip 12.1 RU1
Hope that helps!!