I like Chronos chess clocks.
A chess clock conditions you to think faster and more accurately and promotes fair play.
Chronos GX, the Cadillac of game timers, is made in small production runs in the USA. These timers are in high demand and limited supply, so don't hesitate to get yours now.
Never play a game against a serious opponent without a chess clock. If you do, the following might happen. You are the better player and you move faster than your opponent. He will think over a long period of time and you get impatient. You stop yourself from telling him to move faster, as you don't want to be impolite.
When it is your turn, you move even faster because you are frustrated. Because of your impatience sooner or later you will make a mistake and you get annoyed at yourself. You are at a disadvantage in this game as your opponent can use as much time as he wants and this upsets you. You don't need that much time and wish to play faster. He might use this knowledge to his advantage and think even longer.
To stop this, get a chess clock. They are very practical and will give you a new chess experience. They will bring your chess to the next level. There are fantastic chess clocks around.