Hi I just talked to this manufacture representative USA base co, whose link is below ! Per them one hone model is very effective can generate continuously 5 liters of O2 , 24 hrs good for 5 yrs just in between need to change filters it comes with oxygen tubing and it’s medical grade. Its cost $1195 USA made without international shipping cost !
They can not ship directly internationally but 3rd party can ship to any country !
It operates at 120V, Nepal has 220V it can be converted using converter!!
Check this site and contact them directly to by pass brokers !!!
Tel in USA : 303 536 6000 extension 135
Talk to Christine/ Robert
IF ANY ONE NEEDS HELP DO NOT HESITATE TO CONTACT THEM ! GOOD LUCK THERE ARE OTHER MANUFACTURES SIMILAR PRODUCTS ONE CAN DO QUICK RESEARCH, THESE CAN BE TEMPORARY OPTION FOR AN EMERGENCY!!!