Remington Premier STS 209 Shotshell Primers are manufactured from the highest quality materials and are built to the tightest tolerances to ensure reliable ignition and excellent performance. The dimensions of each primer cup are tightly controlled to 0.0001 inches and they are filled with a special priming mix that guarantees consistency in ignition when used with a variety of powders. These Remington Premier STS 209 Shotshell Primers have been meticulously tested at temperatures from -20 and +150 degrees F to guarantee maximum performance and reliability and they come in either a 1000-piece or 5000-piece box.