calendar bindings of various sizes, binding coil for calendar, calendar binders item name: binding coil material: iron/metal color: various. red, black, white, etc. can be customerized size: different sizes available according to different needs single ring, double ring for choose metal binding coil/meta binding spiral coil/double ring coil inner diameters vary from 6mm to 51mm spiral binding coils also available Established in 2002, Dongguan Taoyuan Stationery Co., Ltd. is a manufacturer specialized in the research, development and production of Notebooks and file folders accessories. Located in Dongguan, with convenient transportation access, Taoyuan Stationery is one of the best and largest suppliers for office file accessories. All of our products comply with international quality standards and are greatly appreciated in a variety of different markets throughout the world. Best quality, good service and fast delivery are always our long-pursue commitment. Following are some of our advantages: 1. About 10 years experience in file clips manufacturing 2. Always keep Upgrade the quality system base on ISO9001:2000 for production 3. Well equipped with completed facilities and professionally skilled employees 4. Environmental-friendly material and quality, SGS test reports can be offered if necessary. 5. OEM service is welcome 6. All of our products are offered in a competitively low price and of high quality. You are most welcomed to visit our factory if you are convenient.