No-hub connection. Bell-type trap is designed into sump area. Replacement strainer covers are sold separately. For Model No. 866-2I (SKU 413822), drain trap 6" x 6", refer to Model No. 866-S2I (SKU 413859) for strainer cover. For Model No. 866-3I (SKU 406787), drain trap 9" x 9", refer to Model No. 866-S3I (SKU 406778) for strainer cover.