ILS Thermal Interface Materials (TIM) - LED Clusters. The ILA-TIM-CLUSTER series, from Intelligent LED Solutions, are a family of thermal heat pads designed specifically for LED clusters. They are available in two sizes with non-adhesive or single/double sided adhesive options.. Features of the ILA-TIM-CLUSTER single-sided and non-adhesive: Colour: pewter 0.13mm thick Temperature range: -240°C to +300°C Features of the ILA-TIM-CLUSTER double-sided: Colour: cream 0.16mm thick Temperature range: -240°C to +300°C