I didn't know this was Art Deco era Napier when I found it--I just thought it was great, and would make mixing cocktails all the more fun. But indeed there is a Napier mark on the tip of the tail, and I know from a little research that it dates to the 1930s or so. The silver plate is in very good condition and polished up easily (and will likely polish up a little more), with just a few minor spots. The jigger holds 1 oz, with a measure mark on one side, and balances on the cat ears when turned upside down to fill. Fun for drinking a shot straight from it, too! 

3 7/8" t x 2 3/4" across at handle; jigger itself is 1 1/2" across.