Once the railing is put together, what is the length of the balusters rail to rail?

Hello, and thank you for your interest in Trex Select Railing. The Select Railing line is offered in 2 finished railing heights of 36" or 42". The round aluminum baluster height for the 36" rail height kit is approximately 32", however the finished installed railing height from the deck surface to the top of the top rail is 36". In addition the baluster height for the 42" rail height kit is approximately 38", however the finished installed railing height is 42" from the deck surface to the top of the top rail. I hope this helps answer your question. Thanks, Tori - Trex Customer Care Team