He’s gorgeous! I would describe his coloring as silver mackerel tabby and white! I think that the reddish patches on his legs are what is called “tarnish”. Sometimes the Inhibitor gene, which causes the silver color, doesn’t block the black pigment completely, so the fur ends up looking reddish in places. Here’s an article that talks more about the genetics of silver cats! SILVER AND GOLD: SMOKE, SHADED AND TIPPED CATS
From the pictures he appears to be blue mackerel tabby and white. Blue tabby and silver tabby are frequently confused, but here is how you can tell the difference:
Blue tabby cats have gray stripes on a beige or cream background.
Silver tabby cats have black stripes on a white or off-white background. When you part the hairs of a silver tabby cat, the base of each hair is white.