Online Parts Store › 3/4" White Plastic Thru-Hull w/Broad Flange Image 1 of 1 3/4" White Plastic Thru-Hull w/Broad Flange $4.71 Molded plastic with broad flange. Per ABYC "Safety Standards for Small Craft". Not recommended for use below the waterline. Add To Cart Added! Molded plastic with broad flange. Per ABYC "Safety Standards for Small Craft". Not recommended for use below the waterline. You Might Also Like 1-1/8" White Plastic Thru-Hull w/Broad Flange $9.81 3/4" Black Plastic Thru-Hull w/Broad Flange $8.00 Seachoice 90 Degree Stainless Steel Covered Thru-Hull $14.56 Seachoice Chrome Plated Plastic Thru-Hull $12.24 5/8" White Plastic Thru-Hull w/Broad Flange $4.34