A block fitting for an air conditioning system comprising: a male block portion having a first annular pilot surrounding a first aperture of the male block portion, the first annular pilot including an axially extending lip formed at an end thereof, having a second annular pilot surrounding a second aperture of the male block portion, the second annular pilot including an axially extending lip formed at a first end thereof; a female block portion having a first annular collar surrounding a first aperture of the female block portion and receiving the first annular pilot of the male block portion, the first aperture of the male block portion and the first aperture of the female block portion substantially concentrically aligned, having a second annular collar surrounding a second aperture of the female block portion and receiving the second annular pilot of the male block portion, the second aperture of the male block portion and the second aperture of the female block portion are substantially concentrically aligned; a first seal structure disposed between the first annular pilot of the male block portion and the first annular collar of the female block portion and a fastener engaging the male block portion with the female block portion to form a substantially fluid tight seal with the first seal structure, wherein one of the male block portion and the female block portion has a stabilizing heel formed adjacent a side surface thereof, the stabilizing heel is disposed along an entirety of the side surface and is configured to militate against transverse dynamic loads on the seal structure in operation and each of the male block portion and the female block portion has a third aperture (118, 154) that receives the fastener, wherein the third aperture of the male block portion is disposed between the first aperture and the second aperture of the male block portion and the stabilizing heel is disposed between the side surface of the male block portion and each of the first aperture, the second aperture and the third aperture of the male block portion. a male block portion having a first annular pilot surrounding a first aperture of the male block portion, the first annular pilot including an axially extending lip formed at an end thereof, having a second annular pilot surrounding a second aperture of the male block portion, the second annular pilot including an axially extending lip formed at a first end thereof; having a first annular pilot surrounding a first aperture of the male block portion, the first annular pilot including an axially extending lip formed at an end thereof, having a second annular pilot surrounding a second aperture of the male block portion, the second annular pilot including an axially extending lip formed at a first end thereof; a female block portion having a first annular collar surrounding a first aperture of the female block portion and receiving the first annular pilot of the male block portion, the first aperture of the male block portion and the first aperture of the female block portion substantially concentrically aligned, having a second annular collar surrounding a second aperture of the female block portion and receiving the second annular pilot of the male block portion, the second aperture of the male block portion and the second aperture of the female block portion are substantially concentrically aligned; having a first annular collar surrounding a first aperture of the female block portion and receiving the first annular pilot of the male block portion, the first aperture of the male block portion and the first aperture of the female block portion substantially concentrically aligned, having a second annular collar surrounding a second aperture of the female block portion and receiving the second annular pilot of the male block portion, the second aperture of the male block portion and the second aperture of the female block portion are substantially concentrically aligned; a first seal structure disposed between the first annular pilot of the male block portion and the first annular collar of the female block portion and a fastener engaging the male block portion with the female block portion to form a substantially fluid tight seal with the first seal structure, wherein one of the male block portion and the female block portion has a stabilizing heel formed adjacent a side surface thereof, the stabilizing heel is disposed along an entirety of the side surface and is configured to militate against transverse dynamic loads on the seal structure in operation and each of the male block portion and the female block portion has a third aperture (118, 154) that receives the fastener, wherein the third aperture of the male block portion is disposed between the first aperture and the second aperture of the male block portion and the stabilizing heel is disposed between the side surface of the male block portion and each of the first aperture, the second aperture and the third aperture of the male block portion. the third aperture of the male block portion is disposed between the first aperture and the second aperture of the male block portion and the stabilizing heel is disposed between the side surface of the male block portion and each of the first aperture, the second aperture and the third aperture of the male block portion.