A mechanical lockdown system for a subsea wellhead connector includes a lockdown member or plate that engages with a tie rod that is connected to the wellhead assembly. The lockdown system includes a support member that is permanently secured to an annular ring through which the tie rod passes. The lockdown system also includes a first handle and a second handle that are installed using a plunger or spring loaded system such that mechanical lockdown system can be easily moved from a lockdown open position to a lockdown engaged position as and when desired with minimal ROV interface.