I would think the back straps alone would weigh close to 5 lbs each, never weighed them honestly, but hell, they are near 20- 24" long if you carve it out tip to stern.
How much meat did you get total? they may have inadvertently mis-labeled, or ground by mistake (trying to be positive, even though you likely got screwed)
“Never be afraid to try something new. Remember, amateurs built the Ark, professionals built the Titanic”
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