The top of the bulkhead has been fitted with 1/8-27NPT for a pressure transducer and an off-set 3/8-16 threaded hole for an eye bolt.
The 1/8-27 NPT was made to fit the 1,600psi transducer unit pictured below. They are available for $30. Ask for one in the comment box at checkout.
These were developed in anticipation of the new Easy Motor from Tele Metrum, one of B`Dales pet projects. The Easy Motor lets you record the chamber pressure of your rocket motor, while in flight. The bulkhead is also fitted with a pair of #6-32 holes. These will be for mounting the electronics board and battery on a 3D printed sled which will be available from our web store soon after the Easy Motors are released. See here.
The liner shoulder incorporates an o-ring acting similarly to a seal disk found in other brands. This feature is strictly for use with convolute phenolic liners. Spiral wound liners must not use this o-ring as damage to the motor may occur.
The face of the bulkhead was milled out to relief weight because hey, who wants big bulky parts? Weighs 154.5g. You may swap out the Standard Commercial Bulkhead for the Experimental Bulkhead with any hardware purchase. ;;; Just tell us so in the comment box at checkout.