Not so much clogged.. But, I have noticed some occasional resistance using some cheaper needles..? 4mm.
What happens is the plastic screw doesn't grip the needle with is sharp at both ends & the end that's meant to penitrate the membrane on the cartridge, doesn't quite.. The needle looks a little longer as its forced in the other direction from the resistance in the rubber?
Like below.. Which can feel like resistance in the bung that pushes the insulin from the ram assembly on the dialled dosage?
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