S4S means this hardwood has been surfaced on all four sides. This board has a cleaner appearance than S2S1E.
Rustic Maple Lumber 22423 4/4 8 pcs 8-10' Irion Lumber Company
Maple Soft 4/4 Lumber - Woodworkers Source
Rough Cut 4/4 (1 in.) Wormy Soft Maple (Ambrosia) 10 Board Foot Pack – Whitewater Forest Products
Hardwood 1Xs Flat Trim Moulding
Soft Maple Lumber - Thompson Hardwoods, Inc.
S4S Hardwood Bundle Bloodwood, Wenge & Birdseye Hard Maple Perfect for Cutting Boards Twelve 12 Pieces 24L X 1.75W X 0.75T
8/4 Ambrosia Maple Lumber // 12 L X 2-8 W, S3S/S4S Wood Boards 2-pack, 4-pack, or 8-pack
The difference in 2x4 lumber from 1946 and 2022 : r/mildlyinteresting
Builders Choice 1 in. x 3 in. x 8 ft. S4S Maple Board HDSM10308X - The Home Depot
Basswood Hardwood S4S
Soft Maple Hardwood Lumber Boards - Surfaced S4S (surfaced four sides) and kiln-dried. This board is more finished than our S2S1E boards and cut from
Maple (Soft) Hardwood S4S