Hoya 58mm Orange G (HMC) Multi-Coated Glass Filter for Black & White Film has been discontinued, here are some related products you might like:
This orange filter darkens blue, violet, green and yellow-green. It particularly useful for all landscape and architectural photography(on black and white film) requiring vivid contours. The sky is distinctly toned with the clouds clearly contrasted against it. It is suitable for landscapes and nature scenes. Multicoated to minimise reflection at the filter surfaces which reduces flare and ghosting.
Filter factor is 2.5 (+1.3 stops)