If you are looking for a reliable and durable lineset for your 9K indoor Olympus unit, you might want to consider the 50ft 1/4 x 3/8 lineset. This lineset is designed to connect the indoor and outdoor units of your mini-split system, ensuring optimal performance and efficiency. The lineset is made of high-quality copper tubing that can withstand high pressures and temperatures. The lineset also comes with pre-flared fittings and insulation that make installation easy and safe. The 50ft length gives you enough flexibility to place your indoor and outdoor units where you want them, without compromising the cooling or heating capacity of your system. The 1/4 x 3/8 size is compatible with most 9K indoor Olympus models, but you should always check the specifications of your unit before purchasing a lineset. The 50ft 1/4 x 3/8 lineset is a great choice for your 9K indoor Olympus unit, as it offers quality, durability and convenience at a reasonable price.