FedEx is betting on bots to help increase the efficiency of its employees.

Since 2016, the company has been using autonomous delivery robots at its equipment repair center in Collierville, Tennessee. Technicians can call the robots to retrieve, move or pick up various parts and tools they need from the stock room without having to leave their work stations.

A newer addition to the team, Sam, works with customers at a FedEx location in New York that also serves as a Samsung repair center. Sam (short for Samsung) carts customers’ broken phones to an on-site technician, and brings them back after they’ve been repaired.

Tracy Bailey is the manager of engineering and innovation at FedEx services, and says he was inspired to try out the robotic workers after seeing their success within the hospitality industry. The idea was to help technicians avoid distractions, such as having to get up to retrieve a part, and focus on a single task.

So Bailey turned to Savioke, a San Jose-based company that specializes in making delivery robots. The company began testing its first butler bot at a California hotel in 2014, and has since expanded to customers in Europe and Asia.

Savioke offers its Relay robot as a leasing service, which costs about $2,000 a month on average, and past customers include Residence Inn, Crowne Plaza, Westin and Aloft.

According to Savioke, Relay has made over 150,000 successful deliveries to date.