What type of lube is best for this double-ended vibrator?

Indulge is compatible with water-based lubricants such as our Smooth Water-Based Personal Lubricant. Smooth is formulated for penile and/or vaginal application, intended to moisturize and lubricate, to enhance the ease and comfort of intimate activity and supplement the body's natural lubrication. Smooth is not compatible with polyurethane condoms.