GrowLab Horticultural Grow Room, 1-Feet 4-Inch by 1-Feet 4-Inch by 3-Feet 11-Inch Increased weight capacity - roof cross-members easily support 100 pounds. Highly reflective interior - significant increase in reflectivity for improved lighting performance. Thermally protected - tent material reflects 97% of all radiant heat for superior insulation. Multiple intake/exhaust ports - including two ports opposite each other at reflector level for air-cooling of lighting system on most models. Waterproof floor - a second floor that is removable for easy cleaning between crops.