Sold as 4 UNITS at $9.84 per unit. (1 unit = each.) Detects toxic stachybotrys. Includes petri dish, mold medium, information form & sterile swab. Test mold in A/C heating systems, bedroom, kitchen/bathroom, attic/basement, RV/boat, pool and pet area. Results in 48 hours. Optional lab analysis available ($30 fee). Clamshell. Manufacturer number: MO 109. SKU #: 5254503. Country of origin: (TBA). Distributed by Professional Laboratories, Inc.