英国采购需求：钥匙扣、个性化金属钥匙扣、定制金属钥匙扣、金属钥匙扣、定制金属钥匙扣、空白金属钥匙扣

I'm looking to place an order for 500 promotional key chains to support my vehicle breakdown business. Each key chain should measure approximately 3 inches in length and width. I'd like the design to prominently feature my telephone number to ensure easy contact for potential customers. Please provide details on customization options, pricing, and estimated delivery time. Looking forward to your response!