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Red Sea Magnesium Pro - Reagent Refill Kit - R21416

Marsoni M251S
Sale price$19.99
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Get it in 3 business days with 1 day shipping. Friday, May 29
Red Sea Magnesium Pro - Reagent Refill Kit - R21416Red Sea's Magnesium Pro Test Kit is an advanced titration test, measuring the level of magnesium in your reef aquarium to an exceptionally high accuracy of 20 ppm. This test kit enables the accurate dosing of Red Sea's Reef Foundation C supplement (magnesium) which is part of the complete Red Sea Reef Care Program. Specifications: Test type: Titration Test range: Accuracy: 20 ppm Titrator included inside easy to use, single hand, high precision
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  • We offer a 30-day return/exchange service after receiving.
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4.2 ★★★★★
Based on 803 reviews
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Verified Purchase
Tom K.
Houston, US
★★★★★ 4
It works as it should...
Size: 96158T-2PCS
Used it in a pinch for stater relay... it works great. Be aware... Mine required metric sockets for the nuts... 10mm for large terminals - 3/8 was too tight and same for smaller terminals 7mm fit better than 5/16 that was too loose. The mounting holes are also spaced closer together than the OEM on a mercruiser 260 in a mid 1980's boat but easy to remedy with a 1/4" drill bit.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on August 4, 2023
D
Verified Purchase
Don
Alexandria, US
★★★★★ 5
Fixed 4.3 Merc IO
Size: 96158T-1PCS
Engine wouldn't start reliably or consistently. I had no clicking either from the old solenoid even though it would start from time to time...motor starts perfect after install. Pretty easy install as long as you reconnect the right wires. This worked perfect!
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Reviewed in the United States on August 8, 2023
M
Verified Purchase
Mr Sexy
Cuba, US
★★★★★ 5
Quality
Size: 96158T-2PCS
Worth the money. Quality. Fit good. Easy too install.
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Reviewed in the United States on September 21, 2025
A
Verified Purchase
Amazon Customer
Phoenix, US
★★★★★ 5
Solenoid replacement
Size: 96158T-2PCS
No changes were needed, fit exactly as the oem. Happy Happy.
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Reviewed in the United States on September 10, 2025
S
Verified Purchase
SOmeone
Lexington, US
★★★★★ 1
Did not work.
Size: 96158T-2PCS
I went to double check that I can read but it says 35hp-275hp and it sure didn’t work on my 200ho mercury so I do not recommend. If you’re on a time crunch don’t push your luck buy OEM like I am doing right after this review.
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Reviewed in the United States on May 13, 2026

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