Mobile Container, stacking, 17-1/2" x 16-1/2" x 15-1/2", injection molded high density polypropylene, six 1/4" drill hole pattern on bottom allows for easy hole insertion for drainage and air circulation, includes: (4) 3" polyurethane swivel casters, clear, Made in USA (Priced per each) Must be purchased in multiples of 2