That depends on the case. The cases for the Scarlet and Violet 151 UPC, the Mega Charizard X UPC and the 30th Anniversary UPC measure 378 x 94 x 223 mm inside; the case for the Pokémon Charizard UPC (white) measures 323 x 94 x 209 mm inside.

The three large UPC cases measure 394 x 104 x 239 mm on the outside, the case for the Pokémon Charizard UPC (white) 339 x 104 x 219 mm.

Yes, the acrylic of all four UPC cases is 96% UV resistant. The walls are 8 mm at the sides and 5 mm at the front.