how to define interface rotational spring in Joint2D

[uyupeng]

element Joint2D $eleTag $Nd1 $Nd2 $Nd3 $Nd4 $NdC <$Mat1 $Mat2 $Mat3 $Mat4> $MatC $LrgDspTag

i know "$MatC uniaxial material tag for rotational spring of the central node that describes shear panel behavior" can use Pinching4
How about $Mat1 $Mat2 $Mat3 $Mat4?
Still Pinching4? If so, could give an eample?
Thank you

[fmk]

you can use whatever uniaxial material you like, if that is the question.

[uyupeng]

got it, thank you