Review on Uxcell PTFE Tube 4 9Ft Transparent by Kenneth Wood

The hose is fine: transparent and slippery. However, the description states that a 3mm diameter thread is suitable. Well, with a 4mm ID tube there is a lot of slack and movement for a 3mm/2.85mm filament. This means the retraction won't work, the flexible filament will bend, the extruder won't be able to produce a constant and even pressure, etc. (all result in crappy prints). it's probably normal. For 3mm/2.85mm filament, look for something with an inner diameter of 3mm to 1/8 inch instead of 4mm.