Introduction
The MOSTRUST Digital Waterproof Shower Clock Timer is a versatile device designed for time management in various environments, including bathrooms and kitchens. It functions as both a clock and a countdown timer, featuring an audible alarm and multiple installation options. Its IPX7 waterproof rating ensures durability in wet conditions.
Package Contents
- 1 x Waterproof Shower Timer
- 1 x User Manual
Product Features
- IPX7 Waterproof Rating: Designed to function properly even when fully submerged in water for short periods.
- Dual Functionality: Operates as both a digital clock and a countdown timer.
- Easy-to-Use Controls: Features 3 quickly adjustable buttons (10min/1min/10sec) for timer settings.
- Multiple Installation Options: Includes a magnetic back, a retractable stand, and a hanging hole for flexible placement.
- Audible Alarm: A gentle alarm sounds for 15 seconds when the timer reaches zero, then automatically turns off.
- Battery Operated: Powered by 1 CR2032 battery (included).
Setup
Battery Installation
- Locate the battery compartment on the back of the timer.
- Open the compartment cover.
- Insert 1 CR2032 battery, ensuring correct polarity (+/-). The battery is included with the timer.
- Securely close the battery compartment cover.
Mounting Options
The timer offers three convenient ways to be placed:
- Magnetic Back: Attach the timer to any metallic surface, such as a refrigerator or a magnetic strip in the shower.
- Retractable Stand: Pull out the integrated stand on the back to place the timer on a countertop or flat surface.
- Hanging Hole: Utilize the hole on the back to hang the timer using a string or hook.

Image: Back view of the timer showing the retractable stand extended.

Image: Back view of the timer highlighting the magnetic pads for secure attachment.
Operating Instructions
Switching Between Clock and Timer Mode
Press the 'CLOCK/TIMER' button to toggle between the clock display and the timer function.
Setting the Clock
While in clock mode, press and hold the 'CLOCK/TIMER' button until the hour digits begin to flash. Use the '10min' and '1min' buttons to adjust the hour, and the '10sec' button to adjust the minutes. Press 'CLOCK/TIMER' again to confirm and exit setting mode.
Setting the Countdown Timer
- Ensure the device is in timer mode.
- Press the '10min', '1min', and '10sec' buttons to set your desired countdown time. The timer can measure up to 99 minutes and 50 seconds.
- Press the 'START/STOP' button to begin the countdown.
- To pause the timer, press 'START/STOP' again. Press it once more to resume.
- To reset the timer, press the 'RESET' button.
Alarm Function
When the countdown timer reaches zero, an audible alarm will sound for 15 seconds and then automatically turn off. This signals the completion of the set time.

Image: Front view of the timer with clearly labeled buttons for 10min, 1min, 10sec, CLOCK/TIMER, START/STOP, and RESET.
Video: Official MOSTRUST video demonstrating the waterproof shower clock timer's features and operation.
Maintenance
Cleaning
Due to its waterproof design, the timer can be rinsed under water. For general cleaning, wipe the device with a soft, damp cloth. Avoid using abrasive cleaners or solvents.
Battery Replacement
When the display dims or the timer functions become erratic, it may be time to replace the CR2032 battery. Follow the battery installation steps outlined in the Setup section.
Troubleshooting
- Timer not responding: Ensure the battery is correctly installed and has sufficient charge. Replace the battery if necessary.
- Display is dim or unreadable: Check battery level. Condensation can also temporarily affect readability; allow the device to dry.
- Difficulty setting the clock/timer: Refer to the 'Operating Instructions' section for detailed steps. Ensure buttons are pressed firmly.
- Alarm not sounding: Verify the timer is counting down correctly. Check if the device has been exposed to extreme conditions that might affect its internal components.
Specifications
| Feature | Detail |
|---|---|
| Brand | MOSTRUST |
| Model Number | MT321 |
| Color | Dark Black |
| Material | Acrylonitrile Butadiene Styrene |
| Product Dimensions | 0.55"D x 3.3"W x 3.3"H |
| Item Weight | 0.352 ounces |
| Power Source | 1 CR2032 battery (included) |
| Waterproof Rating | IPX7 |
Warranty and Support
For warranty information or technical support, please refer to the contact details provided by the manufacturer or retailer at the time of purchase.