Can I used any balusters with this set

Hello, and thank you for your interest in Trex! This listed Transcend railing accessory infill kit a.k.a deck railing completer kit is only designed for square composite balusters for a horizontal application. Please note that if doing a stair application then a different deck railing completer kit would be needed, and if using a different baluster type such as round aluminum or square aluminum a different deck railing completer kit would also be needed. I hope this helps answer your question! Thanks, Tori - Trex Customer Care Team