Buy 3 Primary Antibodies, Get the 4th Free!*

Save on the most trusted antibodies and reagents.

CST's reagents have supported research in over 690,000 publications — reliable results, great value.

Promo code: 2026Q1CST 

Offer period: 5/3/2026 - 29/4/2026

*Terms & Conditions: Offer applies to the purchase of every four (4) qualifying catalog products in the same order, of which the lowest priced qualifying product is free for eligible locations. Eligible locations: Hong Kong and Macau. Promotion code: 2026Q1CST must be referenced when placing an order. No cash or cash equivalent and cannot be sold or otherwise bartered. No substitutions. Offer valid on new catalog orders only, restrictions apply. Offer may not be applied to existing, pending or prior orders, ineligible items, taxes, or shipping and handling charges. Returns of any portion of the purchase will require equal forfeiture of offer or amount equal to offer. All other products/services including but not limited to PTMScan® Services, Antibody Duets, kits, "BSA and Azide Free" antibodies, SignalStar® Multiplex IHC products, InTraSeqTM Single Cell Analysis products, SignalFlexTMM Conjugates, and custom orders are excluded. Cannot be combined with any other promotions or discounts. Void if copied or transferred, where prohibited by law or otherwise restricted. Offer Expires: April 29, 2026. Cell Signaling Technology (together with its subsidiaries, "CST") retains the right to modify or stop the promotion at any time without notice.