Thomas & Betts' Fittings Silver Grip TCF tray/cord fittings are a safe way to terminate portable cord and tray cables in hazardous locations. Hub sizes range from 1/2 in. NPT to 2 in. NPT in aluminum, and from 1/2 in. NPT to 1 in. NPT in 316 stainless steel. The fittings are designed for use in Class I, gas and vapor environments. The chuck was designed to have the extreme pullout strength required for tray cable applications.