Copper-Etchant-Electrolube-FCC250G-Copper-Etchant-Does-Not-Absorb-Moisture-Quickly-Easy-&-Economic-in-use-Safely-Packed-&-Sealed-in-Polythene-Bag-1-66-Specific-Gravity-37-C-Melting-Point-91-8g-100g-water-Solubility-at-20-C-Dissolve-the-Crystals-in-250ml-of-Warm-Water-in-a-Plastic-or-Glass-Vessel-or-in-an-etching-Tank-Stir-to-Dissolve-&-Agitate-Flow-of-Solution-Over-Board-Being-etched-Solution-can-be-Re-used-&-as-it-Becomes-Weaker-Heating-will-Increase-Its-Life-Cont-Supplie