Overview Reviews Product Description 4.70" BACKING PLATE for 3 Jaw Chuck. It is for 1" arbors. Product Videos Custom Field Product Reviews Write a Review Write a Review × Precision Chuck brand BACKING PLATE, 4.70", for 3 Jaw Chuck. 70047 Rating * Select Rating 1 star (worst) 2 stars 3 stars (average) 4 stars 5 stars (best) Name Email * Review Subject * Comments *