Modular design fits any number of wrenches in a set, Patent Pending design, Made in the USA Fits size range 6mm to 38mm or ¼” to 1 ½” Compact design works well with all wrench types including offset, combination, open end, stubby, and ratcheting Identification labels included to easily see wrench sizes Innovative geometry aligns wrenches for a uniform presentation, base has a no-slip feature, Manufacturer: Ernst Manufacturing