Zoom icon Click to expand Tap to zoom Chevron down icon Chevron down icon Button Sprue Bases for Casting Flasks by Grobet Sale $4.90 | / SKU 21-778 1-3/4" - $4.90 2" - $4.90 2-1/2" - $5.44 3" - $5.97 3-1/2" - $6.74 4" - $8.05 1-3/4" 2" 2-1/2" 3" 3-1/2" 4" Diameter Chevron down icon 1 2 3 4 5 6 7 8 9 10+ Quantity Chevron down icon Quantity Add to cart Spinner icon Notify me when back in stock Email address Email me when available Button Sprue Bases for Casting Flasks Matching sprue bases for casting flasks assure a leak-proof seal.