The tekpi of Brunei and the sai of Okinawa bear strong family resemblances. They are both three-pronged forks having a long, thick central tine between two shorter and less substantial ones. The tekpi is primarily an impact weapon, dubbed the Sword Breaker, it can be used to beat bladed weapons away, and of course to beat your opponent purple. There is no catching of blades with the tekpi, neither between the tines nor with crossed central tines. That's crazy. If you understand a little bit about mechanical advantage, two long levers (the sword and the central tine) against your wrists is a recipe for decapitation or "you're not going to believe this but" cocktail conversation. Note- since you will not be catching swords between the tines, it it perfectly ok to have your thumbs or other digits gripping the tekpi between the tines or indeed wielding the tekpi from the "wrong end."
You might think all this fuss about sword breaking is a bit anachronistic and that tekpi have no use for the modern-day, unarmed fighting guy or gal, but you would be wrong. According to Maul, the use of the instruments improves the practitioner's structure, mechanics, manual dexterity, and strength. And why should they not? Tekpi are steel rods. You don't whip them about the air without deriving some noticeable benefits, like heavy, penetrating hand strikes and a vice like pinch grip. When you strike with tekpi, you strike as if wielding a hammer, downwards usually (there are also sidestrikes and uppercuts). Because these instruments are heavy, you must use your entire body (legs and core) to swing them properly.
Proper use of the tekpi makes the weak arm stronger. Traditionally, the tekpi was held in the left hand (for right handed warriors), while the right hand wielded the killing weapon, typically a blade of some sort. This is not unique. In the West, there is a traditional combination of sword and dagger, then of course there are the Samurai. Over the course of time, practice with the tekpi actually makes the weak hand the stronger hand, which is not an unwanted development. According to Maul, the weak hand is actually the more dangerous hand because it is the one used to control the opponent's body and put him into vulnerable positions. Since close quarters, unarmed fighting is very much about controlling the opponent's body to finish the fight, tekpi training is a perfect complement to Silat and a better karate.
Any errors or misinterpretations are my own.