Used oxygen concentrator combo set for sale

Philips oxygen concentrator 5L - use only one month, very new.
Dynmed oxygen concentrator 5L - use less than one year, fully serviced and have changed new fan.
Jeamed portable oxygen concentrator 5L - use less than one month, very new.
For patient who need to use oxygen concentrator for almost 24 hours a day, always recommend to have this combo set, as the machine need to rest and portable machine for traveling to nearest hospital in emergency case.