It is a gray machine installed on the wall at the Krusty Krab. It consists of an orange-brown clock on top which contains yellow numbers and hands. Below there are shelves used for employees to store their cards.
Technologically, it is a time-measuring machine used to determine an employee's tardiness or on-time arrival. Below the clock, there is a slot inside which one must insert their employee card into to activate the machine. Doing so will result in a robotic female voice stating the employee's on-time percentage.
Role in series
"SpongeBob Meets the Strangler"
SpongeBob, arriving at the Krusty Krab early, is waiting in front of this machine for the clock to hit 8:00am, the start of his shift, so he can immediately insert his employee card once the aforementioned time starts. He does so and his on-time percentage is at 100%.
Rather late to work, Squidward inserts his card into the machine, with his on-time percentage being 12%.
Later in the episode, just when the Tattletale Strangler is about to get revenge on SpongeBob when the two are alone at the latter's house, a majority of SpongeBob's friends throw a party for him for having a 100% on-time percentage.
At the beginning of the episode Squidward is waiting for SpongeBob to clock out by inserting his clock in the machine around 6:00 PM, then Squidward does so once SpongeBob does. The machine plays the opposite role in this episode compared to its first appearance.
Despite the Krusty Krab only having two employees, there are more than two employee cards placed in the machine's storage shelves.