31S (silver color) differs from 31B (black color) in nothing but color, so you can safely buy the one that is cheaper at a particular moment if color is not important to you. Look at my photos for an example.
ο»Ώ
Gillette Mach3 Reusable Shaving Razor UEFA Champions League Grey/Black
59 Review
Braun 5-511 Silk-epil 5 Wet & Dry epilator with starter cap, white/blue
61 Review
Experience Precision and Convenience with the Panasonic Cordless Men's Beard Trimmer - ER-GB40-S (Blue)
70 Review
Gillette Fusion5 ProGlide Men's Razor, 1 Cassette, 5 Carbon Blades, FlexBall Technology, Trimmer
81 Review
Titanium Microneedle Roller For Beard And Hair Growth - 540 Needles, Home Use Body Roller With Storage Case
29 Review
Acure Bestselling Duo Kit: Brightening Scrub & Cleansing Gel For All Skin Types - Pomegranate, Blackberry, Acai, Sea Kelp & French Green Clay
38 Review
π« Enhancing Your Senses: Victoria's Secret Pure Seduction Fragrance Mist and Lotion Set
7 Review
π§Ό Maja for Women by Myrurgia, Soap Set - Set of 3, 4.9 Ounces
10 Review