I've tried a few of these with a transfer covering the face of the lighter in a flatbed heatpress. The flip lid half of the lighter always has a slightly blurred print compared to the part of the print on the bottom half.
That is because the flip lid is shifting due to the silicone pad of the heat press allowing it to flex downward under pressure.
You really need to print these with a hard pallet underneath them and they really should be screen printed using the correct inks from Nazdar.
If you just must heat press them then I suggest making a plug that you can slide inside the casing that will hold the flip lid firmly inline with the lower part of the casing.