Multi-lobed seal member

An at least partially sealed structure comprising:

• a receptacle having a continuous top seal face and an interior wall;
• a cap insert having a channel having both a base wall and opening toward said top seal face of said receptacle and an annular indentation with a shelf structure;
• a first seal having first and second opposing engagement surfaces, each with at least one engagement lobe formed thereon, said seal being positioned in said channel with at least two lobes positioned in engagement with said base wall, and said at least other lobe positioned in engagement with said top seal face,
• wherein the number of lobes on said first engagement surface is greater than the number of lobes on said second engagement surface,
• wherein the first seal further comprises an inner circumferential surface and an outer circumferential surface connecting the two engagement surfaces therebetween, and
• wherein the lobes have an arcuate cross section and each lobe has a same height relative to the engagement surface, and
• wherein the at least two lobes are separated by a valley and at least one of the at least two lobes is positioned adjacent to the inner circumferential surface and at least one of the at least two lobes is positioned adjacent to the outer circumferential surface, and
• the at least other lobe is positioned approximately opposite the valley;
• a locking ring engaging said cap insert and said receptacle to compress said seal into engagement with said top seal face and said base wall;
• and
• a second seal having a receptacle engaging surface and a cap insert engaging surface, said second seal being positioned in said annular indentation with the cap insert engaging surface positioned in engagement with at least said shelf structure, and said receptacle engaging surface positioned in engagement with said interior wall.