There are described 11-C-substituted derivatives of erythromycin and pharmaceutically acceptable compositions comprising a therapeutically effective amount of a compound of the invention in combination with a pharmaceutically acceptable carrier. Among the five kinds of inspections, the film quality is measured after resist coating, and before post-coating heat-treatment. The freestanding cover is inserted into a heated compartment in a food warming cabinet and is supported on a retaining mechanism positioned on the shelf of the food warming cabinet. Accordingly, one of the jaw members is provided with a bent flange that cooperates with an edge of the other jaw member in the manner of pliers so that a straggler can be gripped and pulled out.