ARROWHEAD FROST-PROOF WALL HYDRANT INSTALLATION, USE, REPAIR GUIDE [PDF], Arrowhead 456-06LF 1/2" frost free hydrant, length for 3 3/4" wall thickness (shown above) retrieved 2019/08/13, original source: http://champion-arrowhead.com/media/wysiwyg/PDFs/Frost-Free_Hydrant_Guide.pdf Arrowhe...