Minecraft.jar with XRAY preinstalled.
just goto your windows button, goto RUN or search programs and files, and type %appdata% then copy the modded minecraft.jar into the "bin" folder inside then ".minecraft" folder. Push X to turn on xray
NEEDS MODLOADER! This is the undetected Minecraft 1.4_01 XRay mod for beta. Allows you to see through blocks of your choice. Includes cave finder and adjustable light levels. Install 1.4_01 x-ray by adding the class files to your minecraft.ja