137 31mm aluminum cap products are offered for sale by suppliers on Alibaba.com, of which lids, bottle caps & closures accounts for 48%.
A wide variety of 31mm aluminum cap options are available to you, such as plastic, pp and aluminum.You can also choose from bottle, cans and jars 31mm aluminum cap,as well as from non spill, non-refillable, and recyclable 31mm aluminum cap, and whether 31mm aluminum cap is black, white, or gold.