Accurate 4100 is a double-base, slow-burning spherical powder with exceptional metering characteristics. 4100 is an excellent choice for high-performance, full-power loads in magnum handgun cartridges. It is ideally suited for the 357 Mag, 41 Mag, 44 Mag, 454 Casull, 460 S&W, and the 500 S&W. Made in Belgium.