That's exactly right Tim. The flat sawed off parts on the forward bulkhead allow the shake-out of debris. It's the usual round bulkhead but with flat cuts:
The coupler (in this case a jt-60C receives the output from the 24mm white tube. I epoxied a disc to the bulkhead to help hold the coupler in place. All wood surfaces are also coated with epoxy.
And btw Ken is quite right... it's a "chore boy". ONE chore boy can be pulled apart to make three or four replacements for the Aerotech baffle! For a 29mm tube the weight isn't excessive... the one I have for the auction arcas kit I bought comes in at 7 grams... The thing is they'll collect crud and need to be replaced... AND they start to rust and disintegrate too! I replace mine on my Aerotech kits every 6 - 12 flights.