Storm Series Arroyo 3.25" x 3" (12/Pack) Specifically designed for use in all major general hydroponics systems employing 3.25" to 3.75" net pots 1.5 die cut cutout located on the top of the insert will accept the STG 1.5" grow cube as well as the 2" clipper cloner All STG products are pH neutral and require no conditioning or continuous adjustment of your bath due to media influence Non-wicking design allows the grower to feed more often leading to healthier plants and better harvests Open cell design allows for air to move freely through the insert, ensuring the stem stays dry and healthy and the roots beneath receive ambient circulation