Steel C-Profiles galvanized or stainless steel Thermoplastics subject to temperature fluctuations have a significantly higher coefficient of linear expansion than metals. That is why, for some applications, it is better for plastic guides to be held in place by a steel C-profile. (It also makes it easier and faster to replace them.) In many cases, steel profiles are in fact indispensable both for fixing and stabilizing purposes and can be welded or bolted-on where appropriate. Basically we recommend DIN bolts or - a special method - T-head bolts. For details of how to instal steel C-profiles using T-head bolts. Steel C-profiles are available ex stock galvanized or in stainless steel or, on request, in 'black'(untreated surface).