Sturdy metal construction, replace at least once per season. Replacement furnace water pad fits Aprilaire 110, 220, 500, 550, 550A, 558 (10), BestAir BA3200G, Desert Spring DSP-PFT, Hamilton 12HF (EP037), Thermolec 500/550/Pro 600, Evolution Air Pro3000, Honeywell HE100A, HE150A, HE220A/B, HE225A/B, Lasko 5000L, 5000EC, 6000, Lennox WB2-12, WB212 and Chippewa 220.
Unit: EA