Scotchlok connectors
I checked the spec on the Scotchlok 562 tap connectors. They are UL listed for solid and stranded wire and rated at 600 volts.  I have seen them used in manufactured housing before, but rarely.  Here is the link to the manufacturers specifications for this product.  http://solutions.3m.com/wps/portal/3M/en_US/EMDCI/Home/Products/ProductCatalog/~/3M-Scotchlok-Electrical-IDC-562-BOX-Double-Run-or-Tap-Flame-Retardant-Yellow-12-AWG-solid-stranded-10-AWG-stranded-100-per-carton-1000-per-case?N=5430181+4294891913&amp;rt=rud