Hi PilotHawK
The raw material is 3mm hi resistant plastic ! i have been running these lids on my FL for some time,no cracks,breaks etc plus i have tested the air intake tube buy trying to over tighten the hose clamp,and i mean WAY tight,no cracks !
As for sealing,my unit has a pinch mold fitted around the base that seals nicely with the bottom air-box unit,this is the second type molding i tested and its great and very appealing to the eye.
The upper air-box prototype should be close to a reality today.Since i stopped drinking beer back in Jan 05 my creative juice's are flowing like beer itself LOL,whats that i hear you guys say ? an Aussie that doesn't drink beer ! yes its true
Thanks for your interest mate
Aussieduner