Spacers (Shims).

 US$

Add a little extra clear or pink polymer (for your final curings or for your enlargements.) 2 sizes. The large is in 0.4mm while the small is in 2 thicknesses: 0.5mm and 0.8mm:
Small, 0.5mm: Item#5462-05. $75 for 500
Small, 0.8mm: Item#5462-08. $95 for 500
Large, 0.4mm: Item#5466. $50 for 500