Shop for Cleaning Supplies at The Home Depot. Crystal Simple Green industrial heavy-duty cleaner/degreaser formulation is an environmentally safer, cost-effective, water based liquid concentrate that is non-toxic, biodegradable, non-flammable, non-hazardous, phosphate free and non-abrasive. Crystal Simple Green is a clear white to pale straw-colored liquid. No added fragrance. NSF rated A1, A2, A4, A8, B1, C1. VOC compliant to all 2013 regulations.