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Complete Reference Guide to Casio Pro-Trek PRG-270 Watch


Key Points

  • Applicable for Casio Pro-Trek PRG-270-1, PRG-270-2, PRG-270-3, or PRG-270-4 watches

If you want to replace the watch band/strap:

  • First choice – American Perfit OEM Watch Strap (New Jersey, Casio Authorized Parts Distributor) – $28 plus sales tax, and shipping (click here for availability)
  • Second choice – Amazon Generic Replacement Watch Strap – $24 plus sales tax, and shipping or free if you have Prime (click here for availability)
  • Third choice – PacParts OEM Watch Strap (California, Casio Authorized Parts Distributor) – $31 plus sales tax, and shipping (click here for availability)

If you want to replace the watch spring bars:

  • First choice – Amazon Generic Replacement Watch 18mm (length), 1.8mm (diameter) Spring bar’ $6 for four spring bars (click for availability)
  • Second choice – American Perfit 18mm Spring Bars – $3 per spring bar; you will need to buy 2 (click for availability)
  • Third choice – PacParts OEM Watch 18mm Spring Bars – $3 for each spring bar; you will need to buy 2; (click for availability)

If you want to replace the solar battery:

Table of Contents

Identify Your Casio Watch and Module Number

All Casio watches include two numbers etched on the rear metal cover plate of your watch.

The model number will begin with a letter mixed in with letters, numbers and a hyphen. My Pro-Trek watch’s model number is PRG-270.

The module number identifies the internal component of your watch. This number is usually found inside a rectangle “box” and is used to identify the specific user manual (refer to the reference section for the URL) of your Casio watch

Model Information

  • Model Name: Casio Pro-Trek
  • Model Number – PRG-270
  • Module Number – 3415
  • Watch strap size – 27mm / 18mm (Part # 10350859); black resin with silver buckle; waterproof
  • Length: Regular (13 cm, 5.5 cm)

Technical Specifications

  • Super-Full-Auto LED light
    • If the ambient light fades, a turn of your wrist illuminates the watch display particularly brightly.
  • Low-temperature resistant (-10 °C)
    • Even temperatures as low as -10 °C have no effect on this watch.
  • Solar Power
    • A solar cell provides power for operation.
  • Barometer (260 / 1.100 hPa)
    • A special sensor measures the air pressure (measuring range: 260 / 1100 hPa) and presents this on the display in the form of a symbol. This enables early detection of weather trends.
  • Thermometer (-10°C / +60°C)
    • A sensor measures the ambient temperature around the watch and displays it in °C (-10°C /+60°C).
  • Digital-compass
    • A built-in direction sensor detecs the magnetic north.
  • 10,000 m Altimeter
    • A pressure sensor detects changes in the air pressure and converts the result into an altitude up to 10,000 m.
  • Sunrise/sunset display
    • After entering the geographical location, sunrise and sunset times can be displayed for any given date.
  • Height Gain
    • The height gain sums all the meters you have climbed in a session, so that you can see at a glance the total ascent on a tour.
  • Altimeter data memory
    • Depending on the model, up to 40 sets of elevation data can be stored in the watch’s data memory and re-accessed at any time. Each of these data sets consists of a measured altitude as well as the date and time. In addition to the individual altitudes, the maximum and minimum altitudes during a measurement are also stored.
  • World time function
    • Displays the current time in major cities and specific areas around the world.
  • Stopwatch function – 1/10 sec – 1.000 hours
    • Elapsed time, split time and final time are measured with 1/10-sec accuracy. The watch can measure times of up to 1000 hours.
  • Timer – 1/1 min. – 24 hours
    • For fans of precision: the countdown timers help you to remember specific or recurring events by giving off an audible signal at a preset time. The time can be set to the nearest minute and up to 24 hours in advance. Ideal for people who need to take medicines every day or those who do interval training.
  • 5 daily alarms
    • The daily alarm reminds you about recurring events with an acoustic signal at the time you have set. This model has 5 independent alarms for flexible reminders of important appointments.
  • Snooze feature
    • Each time you stop the alarm, it sounds again after a few minutes.
  • Button tones on/off
    • The button tones for using the mode button can be turned off. This means that the watch no longer beeps when switching from one function to another. Preset alarm or countdown timers remain active when the button tones are deactivated.
  • Automatic calendar with Date, Day and Month
    • Once set, the automatic calendar always displays the correct date.
  • 12/24-hour format
    • Times can be displayed in either a 12-hour or 24-hour format.
  • Direction Bezel
    • This bezel can be used to determine approximate directions.
  • Mineral glass
    • The tough mineral glass resists scratching.
  • Resin case
    • The resin housing is the ideal everyday companion. It is durable, lightweight and relatively insensitive to cold, heat or other external influences.
  • Resin band
    • Synthetic resin is the ideal material for wrist straps thanks to its extremely durable and flexible properties.
  • Buckle
    • The bracelet is equipped with a buckle.
  • Battery level indicator
    • An indicator shows the current battery level.
  • Water resistance classification (10 bar)
    • Perfect for swimming and snorkelling: the watch is water resistant to 10 bar according to ISO 22810.
  • Dimensions (H x W x D)
    • 54,6mm x 52,4mm x 14,4mm
  • Weight
    • approx. 67 g

Replacement Parts

  • Screws, back
    • Casio Part # 91041906656 (pack of 6)
    • Casio Part # 74239989 (single screw)
    • Casio Part # SBCS-74239989 (four screws)
  • Screw, sensor cover
    • Casio Part # 91087060757
    • Casio Part # 10393080
  • Back cover
    • Casio Part # 10454915
    • Casio Part # 91087121682
  • Back rubber seal (O-ring)
    • Casio Part # 91087111720
    • Casio Part # 10444053
  • Bezel / resin
    • Casio Part # 91087127525
    • Casio Part # 10450858
  • Decorative Piece, sensor (9H)
    • Casio Part # 91087127526
    • Casio Part # 10450859
  • Cover, sensor (9H)
    • Pac Part # 91087127527
    • Casio Part # 10450850
  • Spring bars (straight)
    • Casio #: 72011384
    • Pac Part # 91049788051
    • Length: 19 mm

Spring Bars

You can either purchase a set of curved or straight spring bars.

I have used replacement curved spring bars in the past but I really did not see any difference between two types.

Curved spring bars and bit more expensive and difficult to find so you should factor that into your purchase consideration.

In a crutch, you can use 1.5 mm diameter spring bars

but larger diameter will bind more to the straps. That in turn increases the tension on the spring bars so it is best to stick with 1.5mm diameter spring bars.

As far as measurements are concerned, please note the length of a spring bar is measured from the tip to the end of a tube.


Straight or Curved?

Tight or loose inside wrist band hole?

Watch Band

Watch bands for Casio Pro-Trek PRG-270 have protruding bumps so most generic replacement straps are not compatible with the watch.

Please note that all genuine Casio watch bands come with metal buckles. Metal buckles also are stamped with CASIO letters.

  • Material: Resin
  • Color: Black
  • SKU: 10450942
  • UPC: 840596100063
  • Fits: CASIO PRG-270-1 and CASIO PROG-270-4
  • Note-1: Buckle – original Casio buckles are metal; knock-off bands usually come in plastic buckle
  • Note-2: Product inscription 826 GE12-18 PUR

Watch Band Loop Holder

Casio Authorized Parts Distributors

If you need warranty work or want Casio to repair your Protrek PRG-270 watch, you can mail your watch to one of two Casio authorized locations (separate location for Canadians)

Before mailing it in, make sure to call and obtain an RMA (Return Merchandise Authorization) number.

East Coast

West Coast


  • Time Central Ltd
  • 240 Riviera Drive, Unit 1
  • Markham, Ontario
  • L3R 5M1
  • email: [email protected]
  • Tel: 1-800-668-7871

Casio Warranty and Repair Service Centers

There are only two authorized repair center locations in the USA: California and New Jersey.

Both locations require the item be sent in for evaluation to determine the cost of the repairs.

West Coast Service Center

  • 2335 HONOLULU AVE.
  • Suite B
  • MONTROSE, CA 91020
  • 818-249-6007
  • There is no pre-registration form available
  • Provide a description of the problem you are experiencing with your full name, shipping address, email and daytime phone number on paper and send with the package

East Coast Service Center

  • For the NJ facility, please use the following site to pre-register your service request:
  • Print and include any relevant document (proof of purchase or receipt)
    • 570 MT. PLEASANT AVE
    • DOVER, NJ 07801
  • If the site does not work:
    1. Provide a description of the problem you are experiencing with your full name, shipping address, email and daytime phone number on paper
    2. Package your product carefully to prevent additional damages to the product
    3. Ship your product to: CASIO REPAIR, 570 MT. PLEASANT AVE, DOVER, NJ 07801
    4. We suggest that your return address is also prominently visible on the outside of the package
    5. Due to the possibility of damage or loss, we recommend insured shipping via FedEx, UPS or US Postal Service
    6. Casio is not responsible for lost or damaged packages in transit from the customer
    7. Please note your product model, serial numbers and tracking information for your own records
    8. Your watch is warranted against manufacturing defects for a period of ONE YEAR from the original purchase date
    9. To obtain warranty service, return your watch to Casio’s Factory Service or Authorized Service Center with a receipt for proof of purchase, clearly showing the date, item purchased, and the retailer from which the purchase was made. Warranty only covers the inner working parts of the watch
    10. Warranty will be denied if the watch was not purchased from an Authorized retailer and if the watch shows signs it was tampered with or opened by anyone other than an approved Authorized Casio Service Technician prior to being sent to Casio’s Service Centers
    11. Repair requests received without proof of purchase, will be processed as an out of warranty repair and will incur the out of warranty charges
    12. For in warranty and out of warranty repairs, Casio may, at its option, repair your watch by installing new or thoroughly reconditioned and inspected components
    13. For in warranty repairs that are no longer repairable due to unavailability of parts or components, we may at our option replace the watch with an identical model or a model with like or similar features
    14. Out of warranty watches that are no longer repairable due to the unavailability of parts or components we may at our option replace the watch with an identical model or a model with like or similar features for a fee. Please note some watches will not have suitable replacement options and will be returned as received and no cost will be charged
    15. The customer shall NOT have any claim under this warranty for repair or adjustment expenses if:
      • The problem is caused by improper, rough or careless treatment;
      • The problem is caused by a fire or other natural calamity;
      • The problem is caused by improper repair or adjustment made by anyone other than a CASIO service center
      • The Case, Band, Crystal, Bezel or battery are worn/damage; Casio will charge for replacing of these parts
      • The proof of purchase is not presented when requesting service
      • If the watch was not originally purchased from an authorized retailer; or
      • The warranty period has expired