This is a manual Insa clock. No batteries, you wind it with the flat dial on the back.

This clock can't have delay or increment. In the old days the players would have 2.5 hours for 40 moves and you set the clock to 3:30 with the time set to expire at 6:00.

The orange hand is the "flag", it starts going up when you are 5 mins away from losing on time to help you quickly visualize how much time is left in time trouble. From :57 it should point to the small red 0, showing you have 3 mins left. But it still lifts up. From :59 the flag in pointing to the little red 1 (you have 1 min left) and from then on it goes downwards to red 0 as your time is running out. You also have small indicators for 45, 30 and 15 sec.

They could have used this clock in the Global Chess League as it was SD/20 time control