4 X Kodak Tri-X 400TX Professional ISO 400, 36mm, Black and White Film Delivers fine grain, wide exposure latitude, high sharpness, and high resolving power Excellent choice for dimly-lit or fast-action subjects Rolls of TRI-X 400 professional black-and-white, 35mm film Perfect for shots requiring a good depth of field, fast shutter speeds, or extending the distance range for flash pictures