Olefins have Supplied & Installed School Sound System. Narayankul Dream Model High School, Pubail, Gazipur, Bangladesh, that founded by School aid Japan foundation & Locally Manage by Basic Development Partner (BPD). We are happy to engage in this project. We Installed TOA Box Speakers Model BS 1034 & 240 Watt TOA Mixer Amplifier Model A-2240. […]