A new highly compact crystal has been introduced by frequency control solutions manufacturer, Precision Devices Inc (PDI). The new C2 crystal consumes only 5.0mm² of PCB real estate with extremely compact dimensions of only 2.5mm (l) x 2.0mm (w) x 0.55mm (d).
HC-49/U series quartz crystal closure. The HC-49/U has an extremely low cost with excellent electrical parameters.
The CX325 surface-mount crystal provides a 3.2 x 2.5 x 0.8 mm footprint
The MS1 crystals are high quality tuning fork resonators manufactured with a photolithographic process

Bliley Technologies’ QC35045 is a low profile and high Q (w/1.25M typical) SC cut crystal that features excellent close in phase noise with a superior aging rate (<30ppm). It comes in a rugged 4-point mechanical HC-37 package with a maximum height of 4.6mm.

UM-1 series quarts crystal
Cardinal Components, Inc. introduces two in a series of crystals in a 5 x 3.2 mm package
Surface-mount (SMD) and Thru-hole crystals