F99 is fingerprint RFID controller;   S99 is RFID controller, no fingerprint;   Choose it carefully mounting Base is optional   F99this is Mini Metal Case Standalone RFID/Fingerprint Access Control with Embedded Design.   Support Fingerprint and 125KHz EM Cards.   It is an ideal choice to install on door frame.   IP66 Waterproof is very sitable for outdoor use.   It support Master card and Master fingerprint for easy opeation.   Feature:   > Embedded Design with Mini size   > Metal case and IP66 Waterproof   > User capacity:800 Fingerprint and 3000 Cards   > One programmable relay operation   > Latch mode to hold door and gate open   > Tri-colour LED status display   Product Name   Mini Metal IP66 Waterproof Fingerprint Standalone Controller support 800 Finger and 3000 Cards   User Capacity   800 Fingerprints and 3000 Cards   Operating Voltage   DC9~24V   Idle Current   25mA   Active Current   100   Proximity Card Reader   EM   Radio Technology   125KHz Proximity Card   Read Range   50px   Wiring Connections   Relay Output, Exit Button   Relay   One (NO, NC, Common)   Adjustable Relay Output Time   o-99 seconds (5 seconds default)   Lock Output Load   2 Amp Maximum   Environment   Meets lP66   Operating Temperature   -25~60 (-13°F ~140°F)   Operating Humidity   20%RH-98%RH   Physical   Zinc-alloy plate   Colour   Silver   Dimensions   L115xW40xH30mm   S99this is Mini Metal Case Standalone RFID Access Control with Embedded Design.   Support 125KHz EM Cards.   It is an ideal choice to install on door frame.   IP66 Waterproof is very sitable for outdoor use.   It support Master card for easy opeation.