How to insert led into a chuck pencil.
1. Get your led and chuck pencil to be used.
2. Bring out the led to be inserted.
3. Press and hold the top button of the chuck pencil.
4. Insert the led into the chuck pencil while the top button is still on hold, make sure you leave small bit of the led outside the pencil.
5. Lastly, release the top button, and you are good to go.
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