How to refill HP inkjet cartridges

Watch the video below to learn how to refill HP inkjet cartridges types 21, 22, 27,28, 56, 57, 60, 74, 75, 92, 93, 94, 95, 122 black in less than two minutes!
"Does it worth?"
Check the example below:
With only 500 ml of ink, you can refill a HP 60 cartridge (5 ml) one hundred times!
This makes each refill cost only $ 0,20 cents!

"Can´t find the rubber feet"
1 - Rubber feets are used under the furniture. They are very cheap.

2 - As an even cheaper alternative, you can use the rubber part of another syringe.

3 - A far more professional alternative, is a device called "SNAP FILL"

"Where the ink is injected?"

Inside view of the HP 60 cartidge.

Compatible with the following printers:
HP Deskjet D2530 D2545 D2560 F4280 HP 21 HP Deskjet D1320 D1330 D1341 D1360 D1420 D1430 D1445 D1455 D1460 D1560 D2320 D2330 D2345 D2360 D2430 D2445 D2460 F335 F340 F350 F380 F1100 F2110 F2140 F2180 F2280 F4135 F4140 F4180 3910
3915 3930 3940 HP psc 1410 HP Officejet J3680 4315 HP Fax 1250 3180