I have two 50amp cables where one end is a female marine twist connection and the other end is a standard 50amp male plug. For the life of me I can't find a pigtail or conversion device that would allow me to connect them to each other. I believe that would require a female standard plug on one end and a male twist lock on the other. Any suggestions?

Say again? So you need twist lock male to dryer outlet female?Might have to build it. Home Depot should have these fittings in the electric isle.

Nema l6-50r to nema 14-50rReferring tohttps://www.generatorjoe.net/html/web/outlet/quailplug.html

You could remove the twist lock from one and install a 50 amp range receptacle.

Does your RV have 'twist lock' for power cord?And you want to connect the TWO 50A cords together .......one plugged into your RV via twist lock and then the other cord connected to that one as an extension cord?IF so....cut the twist lock off one of the cords and replace it with a standard 50A female plug....then you can plug the 'extension cord' into the male plug on the power cord that is connected to your RV via twist lockOr just cut the twist locks off both and replace with standard 50A female plugs

I guess I should have added that one of my 50amp cables is 30' and the other 15'. I use the 15' one whenever I'm close enough to the post since it weighs much less than the 30' one. However, I have to use the longer one about 25% of the time so I don't want to destroy either one. What I'm trying to figure out is how I can connect these two rather than buy a third cable to use as an extension.

Attaching 50amp cables with marine connections | Good Sam Community

Lantley
Nomad
Mar 19, 2018
time2roll wrote:
Then you have 4 cords and twice the connections vs swapping off the end for the common 14-50 connector.

I amazed/impressed that he found the adapter.
I think the adapter is a viable option. The extra connections can be a concern however it does allow the OP to keep his cords and have the option to use them as extension cords if necessary.
time2roll
Nomad
Mar 19, 2018
Then you have 4 cords and twice the connections vs swapping off the end for the common 14-50 connector.
jeffreyhnewby
Explorer
Mar 18, 2018
This is who sells it:

Vincent Surace
Geauga Sales, LLC
216-218-1762
www.AmpUpCords.com
enblethen
Nomad
Mar 18, 2018
Who makes it?
jeffreyhnewby
Explorer
Mar 18, 2018
Here it is:
wa8yxm
Explorer III
Mar 18, 2018
You can get Marinco to Marnco cords but I know of nobody who makes what you want.
Bill_Satellite
Explorer II
Mar 18, 2018
Just go here, http://photoposting.is-great.net/?i=2, insert the picture and copy the ensuing link here!
Greatest thing since sliced bread!
Lantley
Nomad
Mar 18, 2018
jeffreyhnewby wrote:
I appreciate everybody's responses. As it turns out, one response was from a company that sells marine and RV electrical parts and they have exactly what I need. If I could figure out how to post a photo here, I would show you but I don't see that option.

can you give us a link to the site?
jeffreyhnewby
Explorer
Mar 18, 2018
I appreciate everybody's responses. As it turns out, one response was from a company that sells marine and RV electrical parts and they have exactly what I need. If I could figure out how to post a photo here, I would show you but I don't see that option.
Bill_Satellite
Explorer II
Mar 18, 2018
I don't believe that's what he wants. He has a male marine style plug and he needs to connect that to a male RV blade plug. He wants to connect together 2 standard RV power cords. Each has a 50 amp RV plug at one end and a male marine style connector on the other.