Hello PTG1,
Thank you for your question regarding the Delta Lahara® Tissue Holder and I am happy to assist you today.
The thread size for the set screw for this model is 8-32 x 3/8, Cone Point, Hex Socket.
If you could please refer to the email I sent to you or if you could give us a call at 800-345-3358, we will do our best to rectify this issue for you over the phone.
Thank you,
Brandy
Delta Faucet Company
Customer Service
Answered by: Brandy
Date published: 2018-02-14