Proper holders for infrared film?

I have heard that ordinary plastic film holders are not suitable for infrared film, and that old wooden holders are best. I once heard of metal film holders made specifically for IF, but I have not seen them advertized for some time. Does anyone have any first-hand experience in this matter?

Modern plastic holders are fine. There is reputed to be a problem with some hard-rubber darkslides from before the war. For awhile after 1940 darkslides which were IR safe had raised dots on them.

Any holders made since the 1950's should be OK.

the most often made goof with ir film is not shielding the film holder when transferring it from your pack or whatever you are carrying your film in and the camera. always, ALWAYS, shield the film holder from the sun. ir can get past the best light traps and fog, if ever so slightly, the film, and composition you have worked so hard to get. i repeat, because i see it not done so often, always, ALWAYS, shield your film holder from direct or even bright indirect sunlight. until i learned this lesson, i ruined many very good negs. bye.