Just in case it really is a conspiracy and we all march to the Internationalists tune sometime soon: How many digital (electronic) clocks meet FIDE standards? (See below.)
The Chronos—the best clock I have used—does not. Neither does the Saitek Competition Scholastic blue clock or the Excalibur Game Time II.
The Chronos and the Excalibur do not have a dedicated low battery warning signal; the Chronos does not have a mini-users guide affixed to it and the blue Saitek does not support increment. It might take sharp eyes to see who is on move on a Game Time II from 10 meters across a crowded tournament hall.
I fear that the Saitek Competition Pro—the worst clock I have used, or at least the only digital clock I ever had trouble learning to set, (Hi, Keith)—would pass the test. I hope someone points out where I am wrong on that.
That leaves the DGT clocks and…what else?
From: is.gd/8CewG4
[i]Requirements for electronic chess clocks
(a) Clocks must function in full accordance with the FIDE laws of chess.
(b) The display at all times should show the time available to complete a player’s next move.
(c) The displays must be legible from a distance of at least 3 meters.
(d) From at least a distance of 10 meter a player must have a clearly visible indication which clock is running.
(e) In case of passing a time control, a sign on the display must give clear signal which player passed the time limit first.
(f) For battery powered clocks, a low-battery indication is required.
(g) In case of a low-battery indication the clock must continue to function flawless for at least 10 hours.
(h) Special attention should be given to the correct announcement of passing time controls.
(i) In case of accumulative or delay timing systems, the clock should not add any additional time if a player passed the last time control.
(j) In case of time penalties it must be possible that time and move counter corrections are executed by an arbiter within 60 seconds.
(k) It must be impossible to erase or change the data in display with a simple manipulation.
(l) Clocks must contain a short user manual on the clock. Electronic chess clocks used for FIDE events must be endorsed by FIDE Technical Commission… [/i]