About the AP-452 Replacement Lens FootThe AP-452 replaces the stock foot on Nikon Lenses (See list below, Image of compatibility chart, or our website). When installed this support lowers the overall height of the supported lens by about 2". The AP-452 is precision machined to slide right into an Arca-Swiss style quick-release clamp. It also has 1/4" and 3/8" tapped holes for mounting to non-quick-release tripod heads and monopods. All replacement feet feature the same dual safety stops and flash bracket compatibility as our lens plates. For use on the following Lenses Nikon 400 f/2.8 AF-S versions I, II, VR I and VR IINikon 600 f/4 AF-S versions II, VR I, VR IINikon 800 f/5.6 VRWhat's IncludedAP-452 Arca-Swiss Style replacement lens foot (Qty 1)Mounting Screws - M3 x 12mm Socket Head Cap Screw (Qty 4)Safety Stop Screws - M3 x 6mm Socket Head Cap Screw (Qty 2)Hex Key - 2.5mm (Qty 1)10 Year Warranty on all products from WimberleyAbout Wimberley Replacement FeetWe use finite element analysis validated by empirical data when we design our feet. This process allows us to optimize the weight to stiffness ratio. Other manufacturers often reduce weight by removing material in ways that are convenient for the machining process or aesthetic design while ignoring stiffness performance resulting in rigidity below our quality standards.Not compatible with most Manfrotto or Gitzo clamps