DFree and D-pad 4 sheets, junk items

Purchased on Mercari in April 2023.
Never used since purchase.
The main unit is new and unused.
One D-pad was missing from the start, so there are only 4 included, even though the package states 5.
The gel for the sensor has no expiration date. Although it has not been opened, it has been over 2 years since it was likely purchased. Please use it at your own risk. It is included as is.
Although it has been 2 years, the previous seller's purchase date is unknown.
Operation has not been confirmed, so it is being sold as a junk item.
Everything shown in the photos is included.

[From the official website]
DFree is a device that detects bladder fullness with a sensor and notifies you of toilet timing via an app.
[Supports various urination-related concerns] Supports concerns such as anxiety about going out due to frequent urination, wanting to use it for toilet assistance, wanting to use it for children's toilet training, and wanting to visualize urination when you can't feel the urge.
[Diverse usage scenarios] Can be used in various situations such as wanting to take other measures besides diapers or urine pads, wanting to make toilet guidance for caregiving easier, and wanting to prevent bedwetting in children.
[Measures bladder fullness with ultrasound] Uses ultrasound, the same technology as echo examinations, to detect changes in the bladder. The ultrasound is harmless to the human body.
[App notifies you of urination timing] A separate dedicated smartphone app will notify you of urination timing.
[Over 24 hours of continuous operation] Can operate continuously for up to approximately 24 hours on a full charge.

Please refrain from purchasing if you are sensitive or prone to complaints.
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Even if you are in the middle of a discussion or negotiation, the transaction will be with the first person who purchases. Thank you for your understanding.
I have a child with severe physical disabilities at home.
Due to the season, we are prone to illness and have frequent hospitalizations and discharges. Therefore, shipping may take some time. Please consider purchasing only if this is acceptable.
I am raising 6 children, and shipping is only available on weekdays. We are closed on Saturdays, Sundays, and holidays.
Shipping will occur within 4-7 days from the following week.
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