It is "Push-ON D-Shaft" for the following models: this 8s a real marshall knob taken from a tsl 100 head

DSL-201 Combo , DSL-401 ComboCombo , TSL-122Combo , TSL-601Combo , tsl 100 TSL-602Combo , JVM205HHead , JVM210HHead , JVM410H Head , VS15Combo , VS30RCombo , VS65RCombo , VS100RCombo , VS100RHHead , VS102RCombo , VS230Combo , VS265 Combo , AVT20Combo , AVT50 Combo , AVT50HHead , AVT100 Combo , AVT150Combo , AVT150HHead , AVT275Combo ,AS100DCombo , MA50CCombo , MA100CCombo , MG10, MG15, MG15FX, MG30FX, MG50FX, MG100FX, MG100HFX and MG102FX