Thanks to the dual tumbler design of the Lifetime Dual 50 Gallon Composter, you can be mixing one batch of compost while you're putting another to good use in your garden. Constructed of high-density polyethylene (HDPE), these tumblers are durable, UV-protected, and have dark, double-walled panels that absorb and retain heat necessary for proper composting. Ingeniously designed, these composters turn easily on an axis for balanced rotation. This saves you time and energy compared to turning a compost heap. Inside each composter, an internal aeration bar mixes compost and provides air-flow. Last but not least, each one has extra large removable lids and a spring-loaded pin that locks rotation during filling.