These types of connector are designed to be fed through and mounted from the front of a device or panel, serving as a practical means to transmit signals from internal circuitry through a panel. Its design incorporates a flange with two holes, enabling secure attachment via screws or bolts. Front mounting is very common and is particularly suitable for use with thin panels where rear mounting could compromise stability. Care should be taken with mechanical stress or vibration, as the thin panels with which they are commonly used may be susceptible to these influences. 

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Two hole flange panel front mount RF connector