I have a Acer Aspire. I have a Acer Aspire 5715/5315 laptop. I need a power cord for it. All I

Question

I have a Acer Aspire 5715/5315 laptop. I need a power cord for it. All I could find in local shops was a 70w universal power adapter. It doesn't list any Acer products on the partial list on the back. I haven't opened it because if it won't work I will take it back