What is the general refill size of gel pen?

The dimensions of China General Gel Pen refill are as follows:

Outside diameter of refill core tube: about 4.5mm Length of refill core tube: 1 10mm for Korean refills, 1 10mm and1/5 mm for domestic refills ... Flange outside diameter: about 6.5mm.

The inner diameter of the pen mouth (the part where the gel pen tip is clamped) is about 2.5 mm, and the tip of the pen may be slightly thinner. Length from the flange (the part clamped by the pen nozzle for fixing) to the pen tip: about15 mm.

The total length of the refill (from the end of the refill to the nib): 130mm is mostly made in China.

Extended data:

General gel pens have high output and relatively low cost. Moreover, these refills have flanges and are loaded from the head of the pen tube.

Korean and China general gel pens have the same outer diameter and can be used with each other. Generally, gel pens in Japan have the same outer diameter, but the nib is different from the nib, so it is difficult to be universal. Among the gel pens in Japan, only the gel pens developed in11990s can be used universally. Japanese neutral refills developed after 2000 cannot be used by different brands.

In recent years, the inner diameter of the ink tube of neutral refill has changed greatly, and different ink tubes with inner diameters ranging from 2.0mm to 7.0mm have appeared. The amount of ink injected into the ink tube with larger inner diameter is increased from 0.5g/ tube to 2.0g/ tube, and the writing length of a single ink tube is increased from 400-500m to nearly 2000m, which puts forward higher requirements for the ink resistance of the pen head and the sealing and follow-up performance of lithium ester.

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