2nd Gen torx security screws

Ring Doorbell 2nd Gen. I have just purchased the above. The position where the bell will be installed has quite restricted access. My worry is that, due to the situation, during both installation and removal for battery recharging that I could easily lose the small Torx security screws. I note that even in the Spares Parts Kit (currently out of stock) Ring only supplies two extra security screws. I see on-line that similar Torx screws are available from many stockists. Presumably these are compatible with Ring doorbells.. As Ring do not supply bags of the screws as spares, could somebody kindly tell me which is the correct type (size and length) so that I can feel safe to go ahead with the installation and use of the doorbell. If such spares are not suitable, can you offer a solution for the possible problem. Otherwise I shall have to return the doorbell to the retailer for refund.