At $25 + $6 shipping, this seems like a great deal to me.
3-Way CO2 Distribution Bar with Safety - $25 + $6 Shipping
EDIT: This is from a third party seller (kegworks) on Amazon. I've found what appears to be the exact same manifold on kegworks (here). It's selling for $41.75 direct. The description on that indicates that the shut offs do have one way check valves.
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