I need to know what you want.
although i got NFI i would be thinking
1.5" pipe to increase flow rate (over 2")
length to be suitable for 2200w element or generic off the shelf 1" screw in element?
1st option to have XXmm hole in the end of triclover blank for 2200w element
2nd option to have tri-clover cap with 1" BSP thread for 2400w screw-in heating element (or higher W element?)
1/2 bsp male thread inlet / outlet for customer to option with camlocks / barbs etc themselves
other end to have a thread for thermo-well what size thread ?
includes tri-clover clamp
and a mounting bracket tab thing on the side maybe ...
price needs to compete with the hermit coil ? under $100 + element for TAB's