These bricks were produced by a Bayer factory in Filago (Italy) and were used to test clutch power. They were attached on a steel studded base and then grabbed by a vise and detached from the base to measure their tightening strength and its decrease after a certain amount of attach/detach cycles. Judging by the test instrument used, these bricks were made before 2000, 2002 tops.
The bricks are modern: they have cross supports, sidebars, and also inner ribs. They don’t have anything at all written inside.
1×5 colors: Pearl Gray, Dark Blue, Dark Blue-Violet [?], Blue-Violet [?], Sand Blue, Dark Turquoise, Bright Green, Brown, Reddish Brown, ?, Sand Red, Flesh, Orange, Bright Light Orange, Bright Light Yellow, Dark Red, Red, Magenta, Dark Pink, Bright Pink, Pink, White.
1×6 colors: Pearl Gray, Dark Blue, Dark Blue-Violet [?], Sand Blue, Dark Turquoise, Bright Green, Brown, Reddish Brown, ?, Flesh, Curry, Orange, Bright Light Orange, Dark Red, Magenta, Light Flesh.