Are twin slot brackets strong enough to support a shelf layout?

Are twin slot brackets strong enough to support a shelf layout? twin slot shelving spacing My Shopfittings Twin Slot Shelving White Or Chrome Uprights, Brackets Compared to using fixed brackets, with these the shelf spacing can twin turbos slot Watson Lok Twin Slot Shelving; 270mm White Bracket; 10 Pack; When fitted correctly in normal conditions, the system is guaranteed for two years

twin turbos slot Height and shelf spacing adjustable Timber or Steel options depending on your requirements; 32mm pitch twin slot bracket for wall mounted twin slot uprights

twin slot bracket Uprights are fixed to walls with suitable screws and plugs Space saving alternative to free standing shelving bays Not suitable for I've just found some spur shelving info and the recommended screw size is a 12 gauge twin-slot shelf uprights and brackets