Product Description: 

A,Material:plastic POM,Zinc alloy, cold-rolled steel Q235, PA66,spring 65Mn

B,Finish:plated(brass + nickel + sealing) , polish, heat treatment

C,Different colors meet your requirements

Features:

A,Upward opening to 35°, free stop at any position you want.

B,Adjustment according to the door weight is achieved to get a better function.

Product Advantages:

A,Appearance Patent No.: (ZL 2003 3010 1764.2)

B,Using wheel gear inside to avoid skiding , free stop at any position you want.

C,Having a good stability, opening for a labor-saving, closing without noise.

D,YS311 passed 50,000 cycles durability test which is far beyond the CNS requirements of hinge- 40,000 times.

Ps: 

Difference between YS309, YS310, YS311 and YS312 flay stay:

(1) different design

(2) Internal structure:

YS309 flap stay---friction clutch inside

YS310 flap stay---steel ball and cam construction inside

YS311 flap stay---wheel gear inside 

YS312 flap stay---wheel gear inside