Amazon has 2-Pack NOCO NCP2 MC303 Oil-Based Battery Terminal Protectors on sale for $0.97. Shipping is free w/ Prime or on $25+ or $35+ orders (minimum requirement varies by location)
Walmart also has 2-Pack NOCO NCP2 MC303 Oil-Based Battery Terminal Protectors on sale for $0.97. Shipping is free with Walmart+ ( Free 30-Day Trial ) or orders $35 or more. Otherwise, select store pickup where available.