Here is the only site that I found any reference to 38.1 for the D-cel which I was searching for. They call it in their site: Hutchens I Device. and reference the 38.1 spec.
www.cp-racing.com . I searched for the Safety Solutions D-cel. Simpson said that theirs were made by Safety Solutions. [I am still awaiting a call-back from both Simpson and Safety Solutions. I'll pass on anything that I find from either. Doug