2740 BSI 28" also need clips

Thanks for posting. I'm sure we can help, but that stamp only designates the strength of the channel balance. To know its identity, we need to see a version that has the top nylon attachment still intact. The combination of attachments the balance uses determine its identity. If you can show us these we should be able to narrow it down. If by clips you meant the nylon attachments, note all our balances come with these attached. If you mean something else, please specify and send photos and we'd be happy to look into it. 

Thanks for getting back to me. It looks like the bottom fittings has 'wings', or side tabs, but the top fitting lacks them. That matches our S350-28 Channel Balance. For a stamp option, choose 2740. Let me know if you have further questions.