Slow delivery, most likely a drop shipper.
"While the price was good, the overall service was not. I ordered items which appeared to be in stock, and paid for a delivery service which should have been quick. After the estimate delivery time had passed, with no indication anything had been shipped, I contacted Bikeparts. Only then was I given an excuse about problems between their storage warehouse and shipping warehouse, or words to that effect. Surprisingly, after chasing my order, it was shipped and finally arrived a few days later, but long after the original time frame I paid for when placing the order. In reality, I expect they don't hold any stock. They wait for you to order, and drop ship it from another supplier after you do, and probably only if you chase them first. Otherwise you likely won't receive anything!"