材质 ：不锈钢、铁制品两种
表面处理 ：镀锌；不锈钢规格镜面不锈钢
结构功能：翻盖式搭扣；内置锁紧弹簧（结构同65#弹簧双扣一样）
42# spring double buckles
Materials ：There two choices: stainless steel and iron products
Surface process ：Zinc plated, the stainless steel is polished one.
Structure and functions ：Flipping style buckle with inner locking spring.The structure is the same as the spring twin buckles in 65#.