The Laird (TE Connectivity) GMRO is a replacement rubber boot sized for Laird’s mini magnetic NMO antenna mounts, fitting the smaller 2⅜ inch mini magnetic base rather than the full-size 3¼ inch “G-” series covered by the standard GRO boot. The boot fits over the base of the mini magnetic mount to protect painted vehicle roofs and metal surfaces from scratching, and helps keep debris and moisture out from under the magnet. Note that fitting a rubber boot can very slightly reduce the magnet’s holding strength compared to running it bare — worth factoring in for higher-speed or rough-terrain use. A simple, low-cost spare for anyone running mini mag-mount NMO antennas who needs to replace a worn or missing boot.