Hill, Van Santen, Steadman & Simpson
Safety hook
 A safety hook includes a generally R-shaped latch member pivotally mounted on a hook member for opening and closing a mouth of the hook member. The R-shaped latch member includes a ring-shaped head having a pair of spaced resilient support lugs on which pivot pins are formed. The head of the latch member is movably received in a recess in the hook member and the pivot pins are snap-fitted in opening in the hook member. The safety hook can be easily assembled only by forcing the latch member into the recess in the hook member. Once the hook member and the latch member are assembled, they are retained in assembled condition against detachment even when a severe thrusting force is applied onto the locking arm of the latch member. 
Yoshida Kogyo K.K.
Y Y F
Y10S Y10T F16B
additional additional inventional
Tomohiro
Mori