Fire brick / Insulation for HX 70, HX 120, WX 70, WX 75, WX 120 gas heaters from 2001 onwards. More HX & WX Gas Spa Heater Parts Here.

These *must* be replaced once wet, cracked, burnt, etc.

HX 70 & HX 120 - Parts 21 & 22 in Diagram. Also suits WX Wilton Spa Heaters