Czech constructors from the Brisk company assumed the assumption, that the ground electrode in a conventional spark plug limits the spread of the flame front, creating a "shadow zone". An original structure called Premium was created, which is characterized by the absence of a side electrode. The tip of the candle consists of two ring electrodes, separated by an insulating ring and a central electrode. A double surface discharge was used, and the jump of the spark takes place consecutively in three places: first from the center electrode to the first ring electrode (spark A), then between the ring electrodes (spark B), and finally, to the mass of the candle body (spark C). The hop interval is so small, that you can accept, that the sparks jump at the same time. The flame front is spread around the entire circumference of the candle. The most important advantages of this type of candle are: more even engine idling, decrease in fuel consumption, extended durability up to 20 000 km mileage. There are also disadvantages, resulting from not the best self-cleaning properties of the cone, on which the surface discharge occurs. Therefore, these plugs are not recommended for two-stroke engines and worn-out oil-burning engines. In addition, they require an increased ignition voltage.
An extension of the Premium design is the TXS candle by Brisk, which is devoid of the last of the above-mentioned disadvantages, it has kept all the advantages of its predecessor. TXS differs from Premium by removing one insulated ring electrode on the insulator and converting it into three side electrodes. Classic Premium delivered three sparks per ignition, while the TXS candle produces two. The first spark jumps between the silver central electrode and the ring electrode, the other between the ring and one of the three ground electrodes (spark B).