Original Walkera Runner 250 Basic 3 Version RTF RC Quadcopter with OSD/DEVO 7 Transmitter/800TVL HD Camera Super resistance performance. Carbon fiber structure feature durable performance.Extremely long, high sensitive, remote control range.Exteme speed with tactile control, ultra fast speed of 35-40km/h.Simple to disassemble and re-assemble. Customer need to charge the lipo battery fully first, otherwise, the remote cannot sync with the copter. After complete the bind process, customer need to push the left throttle stick to the left bottom to accomplish unlock. Without this step, the copter will not fly, which would cause the customer wrongly think the product is defecitve. If lipo battery or the transmitter battery runs low, or there is signal interference around, the drone may only went 20 feet. The light is flashing, which means the bind process is not completed. To complete this process, customer need to turn on the remote control first, then power on the copter. Flashes waiting for a code. When the aircraft stops blinking for code completion.If customer receive wrong item due to our workers careless, we would offer a free replacement. As we are based in China, it may take some time for the carrier to deliver the package to customer, so sometimes the unit may be damaged by collision in the transit. We would take full responsible for the issue.For missing the propeller blades, some parts are underneath the packing material to save the space. Customer need to take away all packing material in the package to have a look, check underneath the package carefully and thoroughly. The parts are stacked underneath. However, if customer cannot find the part at the end, we would reship the missing part to customer at our cost.