The H25HA Hybrid Vibrator Head is a 1 inch head 15in. long.

It is compatible with SM1E, SM2E, SM3E, SM4E, SM5E, SM7E Wacker Neuson concrete vibrator shafts.

It is compatible with the  Wacker Neuson electric motors concrete vibrator motors models M1500 and M2500.  Not compatible with gas powered concrete vibrator motor