The AllPoints Foodservice Parts & Supplies 1021206 Guardian™ Drain Lock features a 4-1/2" outer diameter designed to fit 4" diameter floor drains. Its dome shape ensures effective drainage while preventing debris from entering the system. Constructed with a durable aluminum dome and a sturdy plastic collar, this drain lock provides reliable performance and longevity, making it an essential accessory for maintaining clean and efficient drainage in foodservice environments.