1. The craftsmanship is the quality assurance of the frame, and the quality of the craftsmanship of a pair of frames is often reflected in the details.

(1) Whether the two temples are flat.

Place the frame flat on the table to see if the contact point is free. If there is a situation where one side is high and the other is low, it is necessary to ask professionals to adjust the temples to achieve the effect of left and right balance and up and down symmetry.

(2) Pay more attention near the welding point of the metal frame to see if there are any cracks.

Due to the thermal effect during welding, the stress structure of the material is changed, or it is prone to fracture when subjected to force due to virtual welding, material fatigue, etc.

(3) Pay attention to whether the stipules of the frame are symmetrical on both sides and whether the fixation is safe.

(4) Open and close the temples and feel the elasticity.

It is generally wrong to think that the tighter the better, which means that the lubricating degree of the screw is not enough, and it is easy to cause damage to the temple. Too loose is not good, and the screw may not be tightened. Moderate tightness is best.