Supra C3 Alphabet Dial model, By GE is the oldest and most recognized brand name of lockbox and they have hundreds of models. This Guide is for the C3 Alphabet Model. The ratings guide below is based off of my experience as a homeowner, Real Estate Investor, and the experience of those that I personally know that have used the Supra Lockboxes.
Each of these Categories are rated on a scale of 1 to 10
“1” being poorest “10” being the best.
“1” being poorest “10” being the best.
Quality “7”
PROS: The Supra lockbox itself has an all-metal construction with a removable front door that is very well engineered. The C3 Alpha dial also comes with a custom fit rubber cover to prevent damage from the elements and abuse.
CONS: The removable front door can be hard to remove in cold weather and long fingernails sometimes have problems opening the latch if not closed properly.
Ease of Use: “4”
PROS: The alpha dial is handy to form combinations of 3 letter words that are easier to recognize.
CONS: The alpha dial process is cumbersome and difficult. It functions exactly like a locker room combination.
Changing the Combination With Ease: “10”
PROS: Make handy 3 letter words that are easy to remember.
CONS: You will need a screwdriver and a little patience to change the combo here. Difficult and unclear on how it works, and requires some practice to get good at it.
Security: “6”
PROS: The C3 Alpha Dial Combination resets every time it is open so you will always know that once the lockbox is close it is secure.
CONS: The front door on the C3 completely removes to give you access to the keys. If this door ever gets lost. The box becomes useless. Anyone that has opened the box has easy access to the hasp release that would allow them to remove the lockbox. (I have had some lockboxes stolen using this method.)
Price: “3”
PROS: The Supra C3 is the most recognized and oldest brand on the market.
CONS: The Supra C3 is the most expensive lockbox on the market.
Features: These are important to note features to know when making your buying decision:
1. Comes with Protective Cover: All C3s ship with a protective solid rubber cover, which prevents the lockbox from damage from the elements, and wear and tear.
2. Easy to install: There is no easier lockbox to install than the SUPRA C3 just slide the hasp over the doorknob and close it and it locks tight. Anyone with no practice can install this box in under 5 seconds.
3. Appearance: The SUPRA C3 pushbutton is the most recognized and popular lockbox used by realtors and investors nationwide. The look is professional and well recognized.
SUPRA C3 is a great solution for your key storage and security needs. Here is a list of just a few of the uses my clients have purchased them for.
· Real Estate & Property Management
· Maintenance People & Cleaning Personnel
· After School Access for Children
· Easy Access for Friends and Family
· Emergency Access for the Elderly
· Construction Sites & Vehicles
· Contractors & Subcontractors
· Recreational Vehicles
· Boats & Boat Lockers
· Bicycles and Motor Bikes
· Vacation Properties & Rentals
· Great for Joggers & Outdoor Sports!
· And anywhere having access to keys unattended is a priority
Never leave your keys under the mat again keep the keys to you house in a safe and secure place.
The Supra C3 Also has a lever adapter so that can easily fit on any style of door whether is it a knob or a lever.
Guide created: 07/14/06 (updated 07/03/08)


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