You need only 1-pair. Tell your ID to use "3-layer Steel Track", translated from Mandarin. This tracks will allow you to pull your drawer out fully. It's heavy duty and slides smoothly. But most importantly is the base plank, must be at least 15mm, if can 20mm is best.
Or can get the "BLUM" Soft Closing Runners, they are the best, but will incur more cost.