Just as I warned the price on these filters just jumped from $19.57 to $136.70. If/When you do run across a good deal buy them immediately because the price can suddenly fluctuate wildly. Same thing just happened to a 100 pack of 1 micron 12.5cm glass microfiber filters, price went from $39 to $231 overnight. The first time I bought glass microfiber filters I only bought 100 and got them for $25. Once I decided they were my filter of choice the same 100 pack cost $125 so I waited and periodically shopped them waiting for another good deal. Eighteen months later I found them for under $20 per hundred and bought enough to last a lifetime.