This is a whistle valve with 3/8 x 32 threads, to fit 1/4 pipe. it has a 3/8 x 32 female thread in top and bottom
The valve body is 1.1/8″ tall. the hexagon part is 9/16″ across the flats and the main body is approx 3/4″ wide
The lever is sprung loaded to pull with a chain.