LavaLockBlacktemp probe Grommets are high heat silicon and work with a variety smokers. The channel is approx 1/8" so it will fit all smokers with metal gauge around 11 gauge or 1/8" thick (+/- a couple of gauges) Made from Soft Silicon Rubber, for a great fit and seal. No drill installation for Weber Smokey Mountain 14.5 18.5 or 22.5, and other models like some Treager, GMG, custom smokers and most COS smokers. The 1.25" hole fits Weber Smokey Mountain perfectly. 1.25" in probe port for 1" hole LL_PP255M probe port 1" 1.25" OD 1.5" for 1.25" hole LL_PP32M probe port 1.25" 1.5 od, fits weber smokey mountain Installation tips (for non-Smokey Mountain Cooker grills): 1.) Use a 1 in or 1-1/4" drill bit made for drilling metal. 2.) Use a corded drill (or a high power cordless drill) for best results. 3.) Install just above grate level for most accurate temperature reading. Use a knife to cut the probe insertion hole along the "X" line before installation, to prevent the grommet from falling when the probe is inserted for the first time. We recommend installing with LavaLock-or other-RTV to ensure a tight fit!