GSM is the mat's published area weight
For the current Samrat Poly Resins range, CSM 300 means a published area weight of 300 g/m² and CSM 450 means 450 g/m². GSM is an area-weight reference; it is not, by itself, a complete statement of final laminate thickness, structural capacity, resin consumption or number of layers.
Compare the component before comparing the numbers
Start with the part being made: roofing sheet, tank, panel, door, moulded product or another documented FRP component. Then review the drawing, required reinforcement build-up, geometry, approved resin system and process. These are the facts that turn a CSM weight into a meaningful procurement discussion.
The site does not publish a rule that assigns CSM 300 or CSM 450 to every application. Avoid treating one mat weight as a universal replacement for the other without the component requirement.
Do not convert GSM into an unsupported thickness claim
Buyers may search for 'glass fiber thickness' or 'glass fiber layers'. The published product data supports the two area weights, but it does not publish a final laminate thickness, a layer count or a load rating for a particular component. Those outcomes depend on the broader material system and component design.
What to include in a CSM quotation request
State whether CSM 300 or CSM 450 is requested or under consideration, the intended FRP component, expected quantity, delivery location and any drawing or purchase specification. Add the resin system under review where known. This is more useful than requesting only 'glass fibre mat' without application context.