What is the difference between Timberland's and Timberland's Pro series?

During 1999 Timberland expanded its product line with the introduction of two subbrands: Mountain Athletics and Timberland PRO. The Mountain Athletics line included performance footwear specifically designed for outdoor sports, including trail running, bouldering, and scrambling; it was also aimed at a younger group of consumers than the Timberland brand. Timberland PRO was a line of work boots designed for professional tradesmen, with the individual models containing some or all of these features: waterproofing, insulation, steel toe, slip resistence, and protection from electrical hazards.

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