Saltfire ST-X8 Tall DEFRA Approved Wood Burning Stove. TheSaltfire ST-X8 Tall is an DEFRA Approved Multifuel Stove. Defra ApprovedYes. Eco Design 2022 Ready (Future Proofed). Ultra-Clean Burning. TheST-X8 Tall has a particularlylarge firebox for an 8kW model allowing a greater range of heat output and forlarger logs to be burned.