A 1 meter long coil with 0.5 mm ID has a volume of 196 µl.  therefore you would need 1.9 meter long coil. As we do not offer a reaction coil with such length needed for 375µl volume, I suggest you purchase 8 meters of PTFE tubing with 0.2 mm ID (MTC catalog number 49210-20)  and makes a coil from the tubing.

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