/ JOE'S ROCKET EMPORIUM › ESTES ROCKET ENGINE MOUNTING BLOCK. DESIGNED TO FIT 18MM STANDARD ROCKET ENGINE BODIES Image 1 of 2 Image 2 of 2 ESTES ROCKET ENGINE MOUNTING BLOCK. DESIGNED TO FIT 18MM STANDARD ROCKET ENGINE BODIES $4.95 THIS ADAPTER BLOCK ALLOWS HOME BUILDERS THE CAPABILITY OF BUILDING ROCKET FROM SCRATCH FROM 1.25 INCH CARDBOARD TUBE Add To Cart Added! THIS ADAPTER BLOCK ALLOWS HOME BUILDERS THE CAPABILITY OF BUILDING ROCKET FROM SCRATCH FROM 1.25 INCH CARDBOARD TUBE