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.