SENNHEISER XSW-D Pedalboard Set Battery Degradation

The price may be a bit high as I'm unsure of the market value. Please feel free to negotiate or ask any questions.

*Since this item is also listed on other sites, I will do my best to keep track, but it would be greatly appreciated if you could confirm the stock in the comments before purchasing.

This is the XSW-D Pedalboard Set from SENNHEISER.

It is a wireless system for instruments such as guitars and basses.

I've tried quite a few major digital wireless systems, including SHURE, but personally, I felt this one had the best sound (my favorite sound).

I purchased it new and used it for a while.

The receiver, transmitter, and genuine AC adapter are included.
As for the other minor accessories, I don't recall using them, so it's likely that nothing is missing.

Regarding the transmitter's battery:
Even when starting from a full charge,
it blinks red after about 20 minutes,
and the battery runs out about 30 minutes after that (about 50 minutes from the start).
(Please consider this as a rough estimate, as the battery life may vary slightly depending on the radio wave environment, etc.)

Would this be suitable for someone who plans to replace the battery or can use it with the current battery life?

Other than the above, there are no other issues, noticeable scratches/stains, and the operation is good.

It will be shipped in the original box shown in the photos, wrapped in bubble wrap.

[Brand] SENNHEISER
[Model] XSW-D Pedalboard Set
[Color] Black

Thank you.
SENNHEISER XSW-D Pedalboard Set Receiver SENNHEISER XSW-D-PED-RECEIVER
Brand: SENNHEISER
SENNHEISER XS Wireless Digital (XSW-D) Pedalboard Set [Domestic Genuine Product] 508486
Brand: -

SENNHEISER XSW-D Pedalboard Set Wireless System for Guitar/Bass Battery Degradation